Table of Contents
This chapter describes MySQL Connectors, drivers that provide connectivity to the MySQL server for client programs.
MySQL provides support for ODBC by means of MySQL Connector/ODBC, the family of MyODBC drivers. This is the reference for the Connector/ODBC product family of MyODBC drivers that provide ODBC 3.5x compliant access to the MySQL Database System. It teaches you how to install MyODBC and how to use it. There is also information about common programs that are known to work with MyODBC and answers to some of the most frequently asked questions about MyODBC.
This reference applies to MyODBC 3.51. You can find a manual for an older version of MyODBC in the binary or source distribution for that version.
This is a reference to the MySQL ODBC drivers, not a general ODBC reference. For more information about ODBC, refer to http://www.microsoft.com/data/.
The application development part of this reference assumes a good working knowledge of C, general DBMS knowledge, and finally, but not least, familiarity with MySQL. For more information about MySQL functionality and its syntax, refer to http://dev.mysql.com/doc/.
If you have questions that are not answered in this document, please
send a mail message to <[email protected]>
.
ODBC (Open Database Connectivity) provides a way for client programs to access a wide range of databases or data sources. ODBC is a standardized API that allows connections to SQL database servers. It was developed according to the specifications of the SQL Access Group and defines a set of function calls, error codes, and data types that can be used to develop database-independent applications. ODBC usually is used when database independence or simultaneous access to different data sources is required.
For more information about ODBC, refer to http://www.microsoft.com/data/.
Connector/ODBC is the term designating the MySQL AB product family of MySQL ODBC drivers. These are known as the MyODBC drivers.
MyODBC 2.50 is a 32-bit ODBC driver from MySQL AB that is based on ODBC 2.50 specification level 0 (with level 1 and 2 features). This is one of the most popular ODBC drivers in the Open Source market, used by many users to access the MySQL functionality.
MyODBC 3.51 is a 32-bit ODBC driver, also known as the MySQL ODBC 3.51 driver. This version is enhanced compared to the existing MyODBC 2.50 driver. It has support for ODBC 3.5x specification level 1 (complete core API + level 2 features) in order to continue to provide all functionality of ODBC for accessing MySQL.
MySQL AB distributes all its products under the General Public License (GPL). You can get a copy of the latest version of MyODBC binaries and sources from the MySQL AB Web site http://dev.mysql.com/downloads/.
For more information about MyODBC, visit http://www.mysql.com/products/myodbc/.
For more information about licensing, visit http://www.mysql.com/company/legal/licensing/.
MyODBC can be used on all major platforms supported by MySQL, such as:
Windows 95, 98, Me, NT, 2000, XP, and 2003
All Unix Operating Systems
AIX
Amiga
BSDI
DEC
FreeBSD
HP-UX 10, 11
Linux
Mac OS X Server
Mac OS X
NetBSD
OpenBSD
OS/2
SGI Irix
Solaris
SunOS
SCO OpenServer
SCO UnixWare
Tru64 Unix
If a binary distribution is not available for downloading for a
particular platform, you can build the driver yourself by
downloading the driver sources. You can contribute the binaries
to MySQL by sending a mail message to
<[email protected]>
, so that it becomes
available for other users.
MySQL AB provides assistance to the user community by means of
its mailing lists. For MyODBC-related issues, you can get help
from experienced users by using the
<[email protected]>
mailing list.
For information about subscribing to MySQL mailing lists or to browse list archives, visit http://lists.mysql.com/. See Section 1.7.1, “MySQL Mailing Lists”.
Of particular interest is the ODBC forum in the MySQL Connectors section of the forums.
Community support from experienced users is available through the MySQL Forums, located at http://forums.mysql.com. See Section 1.7.2, “MySQL Community Support at the MySQL Forums”.
If you encounter difficulties or problems with MyODBC, you
should start by making a log file from the ODBC
Manager
(the log you get when requesting logs from
ODBC ADMIN
) and MyODBC. The procedure for
doing this is described in Section 26.1.9.7, “Getting an ODBC Trace File”.
Check the MyODBC trace file to find out what could be wrong. You
should be able to determine what statements were issued by
searching for the string >mysql_real_query
in the myodbc.log
file.
You should also try issuing the statements from the
mysql client program or from
admndemo
. This helps you determine whether
the error is in MyODBC or MySQL.
If you find out something is wrong, please only send the
relevant rows (maximum 40 rows) to the myodbc
mailing list. See Section 1.7.1, “MySQL Mailing Lists”. Please never
send the whole MyODBC or ODBC log file!
If you are unable to find out what's wrong, the last option is
to create an archive in tar or Zip format
that contains a MyODBC trace file, the ODBC log file, and a
README
file that explains the problem. You
can send this to
ftp://ftp.mysql.com/pub/mysql/upload/. Only we at
MySQL AB has access to the files you upload, and we are very
discreet with the data.
If you can create a program that also demonstrates the problem, please include it in the archive as well.
If the program works with some other SQL server, you should include an ODBC log file where you do exactly the same thing in the other SQL server.
Remember that the more information you can supply to us, the more likely it is that we can fix the problem.
You can send a patch or suggest a better solution for any
existing code or problems by sending a mail message to
<[email protected]>
.
Open Database Connectivity (ODBC) is a widely accepted application-programming interface (API) for database access. It is based on the Call-Level Interface (CLI) specifications from X/Open and ISO/IEC for database APIs and uses Structured Query Language (SQL) as its database access language.
A survey of ODBC functions supported by MyODBC is given at Section 26.1.16, “MyODBC API Reference”. For general information about ODBC, see http://www.microsoft.com/data/.
The MyODBC architecture is based on five components, as shown in the following diagram:
Application:
An application is a program that calls the ODBC API to access the data from the MySQL server. The Application communicates with the Driver Manager using the standard ODBC calls. The Application does not care where the data is stored, how it is stored, or even how the system is configured to access the data. It needs to know only the Data Source Name (DSN).
A number of tasks are common to all applications, no matter how they use ODBC. These tasks are:
Selecting the MySQL server and connecting to it
Submitting SQL statements for execution
Retrieving results (if any)
Processing errors
Committing or rolling back the transaction enclosing the SQL statement
Disconnecting from the MySQL server
Because most data access work is done with SQL, the primary tasks for applications that use ODBC are submitting SQL statements and retrieving any results generated by those statements.
Driver manager:
The Driver Manager is a library that manages communication between application and driver or drivers. It performs the following tasks:
Resolves Data Source Names (DSN)
Driver loading and unloading
Processes ODBC function calls or passes them to the driver
MyODBC Driver:
The MyODBC driver is a library that implements the functions in the ODBC API. It processes ODBC function calls, submits SQL requests to MySQL server, and returns results back to the application. If necessary, the driver modifies an application's request so that the request conforms to syntax supported by the MySQL.
ODBC.INI:
ODBC.INI
is the ODBC configuration file
that stores the driver and database information required to
connect to the server. It is used by the Driver Manager to
determine which driver to be loaded using the Data Source
Name. The driver uses this to read connection parameters
based on the DSN specified. For more information,
Section 26.1.9, “MyODBC Configuration”.
MySQL Server:
The MySQL server is the source of data. MySQL is:
A database management system (DBMS)
A relational database management system (RDBMS)
Open Source Software
An ODBC Driver Manager is a library that manages communication between the ODBC-aware application and any drivers. Its main functionality includes:
Resolving Data Source Names (DSN)
Driver loading and unloading
Processing ODBC function calls or passing them to the driver
The following driver managers are commonly used:
Microsoft Windows ODBC Driver Manager
(odbc32.dll
),
http://www.microsoft.com/data/
unixODBC Driver Manager for Unix
(libodbc.so
),
http://www.unixodbc.org.
iODBC ODBC Driver Manager for Unix
(libiodbc.so
),
http://www.iodbc.org
MyODBC 3.51 also is shipped with UnixODBC beginning with version 2.1.2.
MySQL AB supports two Open Source ODBC drivers for accessing MySQL functionality through the ODBC API: MyODBC (MyODBC 2.50) and MySQL ODBC 3.51 Driver (MyODBC 3.51).
Note: From this section onward, we refer both the drivers generically as MyODBC. Whenever there is a difference, we use the original names.
MyODBC works on Windows 9x, Me, NT, 2000, XP, and 2003, and on most Unix platforms.
MyODBC is Open Source. You can find the newest version at http://dev.mysql.com/downloads/connector/odbc/. Please note that the 2.50.x versions are LGPL licensed, whereas the 3.51.x versions are GPL licensed.
If you have problem with MyODBC and your program also works with OLEDB, you should try the OLEDB driver.
Normally you need to install MyODBC only on Windows machines. You need MyODBC for Unix only if you have a program like ColdFusion that is running on a Unix machine and uses ODBC to connect for database access.
If you want to install MyODBC on a Unix box, you also need an ODBC manager. MyODBC is known to work with most Unix ODBC managers.
To make a connection to a Unix box from a Windows box with an ODBC application (one that doesn't support MySQL natively), you must first install MyODBC on the Windows machine.
The user and Windows machine must have access privileges for
the MySQL server on the Unix machine. This is set up with the
GRANT
command. See Section 13.5.1.3, “GRANT
and REVOKE
Syntax”.
You must create an ODBC DSN entry as follows:
Open the Control Panel on the Windows machine.
Double-click the ODBC Data Sources
32-bit
icon.
Click the tab User DSN
.
Click the Add
button.
Select MySQL in the screen Create New Data
Source
and click the Finish
button.
The MySQL Driver default configuration screen is shown. See Section 26.1.9.2, “Configuring a MyODBC DSN on Windows”.
Start your application and select the ODBC driver with the DSN that you specified in the ODBC administrator.
Notice that other configuration options are shown on the MySQL screen that you can try if you run into problems (options such as trace, don't prompt on connect, and so forth).
To install MyODBC on Windows, you should download the appropriate
distribution file from
http://dev.mysql.com/downloads/connector/odbc/, unpack it, and
execute the
MyODBC-VERSION
.exe
file.
On Windows, you may get the following error when trying to install the older MyODBC 2.50 driver:
An error occurred while copying C:\WINDOWS\SYSTEM\MFC30.DLL. Restart Windows and try installing again (before running any applications which use ODBC)
The problem is that some other program is using ODBC. Because of
how Windows is designed, you may not be able in this case to
install new ODBC drivers with Microsoft's ODBC setup program. In
most cases, you can continue by pressing Ignore
to copy the rest of the MyODBC files and the final installation
should still work. If it doesn't, the solution is to re-boot your
computer in “safe mode.” Choose safe mode by pressing
F8 just before your machine starts Windows during re-booting,
install MyODBC, and re-boot to normal mode.
To install or upgrade MyODBC from an RPM distribution on Linux,
simply download the RPM distribution of the latest version of
MyODBC and follow the instructions below. Use su
root to become root
, then install
the RPM file.
If you are installing for the first time:
shell>su root
shell>rpm -ivh MyODBC-3.51.01.i386-1.rpm
If the driver exists, upgrade it like this:
shell>su root
shell>rpm -Uvh MyODBC-3.51.01.i386-1.rpm
If there is any dependency error for MySQL client library,
libmysqlclient
, simply ignore it by supplying
the --nodeps
option, and then make sure the
MySQL client shared library is in the path or set through
LD_LIBRARY_PATH
.
This installs the driver libraries and related documents to
/usr/local/lib
and
/usr/share/doc/MyODBC
respectively. Proceed
onto Section 26.1.9.3, “Configuring a MyODBC DSN on Unix”.
To uninstall the driver, become
root
and execute an rpm
command:
shell>su root
shell>rpm -e MyODBC
To install the driver from a tarball distribution
(.tar.gz
file), download the latest version
of the driver for your operating system and follow these steps:
shell>su root
shell>gunzip MyODBC-3.51.01-i686-pc-linux.tar.gz
shell>tar xvf MyODBC-3.51.01-i686-pc-linux.tar
shell>cd MyODBC-3.51.01-i686-pc-linux
Read the installation instructions in the
INSTALL-BINARY
file and execute these
commands.
shell>cp libmyodbc* /usr/local/lib
shell>cp odbc.ini /usr/local/etc
shell>export ODBCINI=/usr/local/etc/odbc.ini
Then proceed on to Section 26.1.9.3, “Configuring a MyODBC DSN on Unix”, to configure
the DSN for MyODBC. For more information, refer to the
INSTALL-BINARY
file that comes with your
distribution.
MDAC, Microsoft Data Access SDK from http://www.microsoft.com/data/.
MySQL client libraries and include files from MySQL 4.0.0 or higher. (Preferably MySQL 4.0.16 or higher). This is required because MyODBC uses new calls and structures that exist only starting from this version of the library. To get the client libraries and include files, visit http://dev.mysql.com/downloads/.
MyODBC 3.51 source distributions include
Makefiles
that uses
nmake. In the distribution, you can find
Makefile
for building the release version
and Makefile_debug
for building debugging
versions of the driver libraries and DLLs.
To build the driver, use this procedure:
Download and extract the sources to a folder, then change
location into that folder. The following command assumes the
folder is named myodbc3-src
:
C:\> cd myodbc3-src
Edit Makefile
to specify the correct
path for the MySQL client libraries and header files. Then
use the following commands to build and install the release
version:
C:\>nmake -f Makefile
C:\>nmake -f Makefile install
nmake -f Makefile builds the release
version of the driver and places the binaries in
subdirectory called Release
.
nmake -f Makefile install installs
(copies) the driver DLLs and
libraries(myodbc3.dll
,
myodbc3.lib
) to your system directory.
To build the debug version, use
Makefile_Debug
rather than
Makefile
, as shown below:
C:\>nmake -f Makefile_debug
C:\>nmake -f Makefile_debug install
You can clean and rebuild the driver by using:
C:\>nmake -f Makefile clean
C:\>nmake -f Makefile install
Note:
Make sure to specify the correct MySQL client libraries and
header files path in the Makefiles (set the
MYSQL_LIB_PATH
and
MYSQL_INCLUDE_PATH
variables). The
default header file path is assumed to be
C:\mysql\include
. The default library
path is assumed to be C:\mysql\lib\opt
for release DLLs and C:\mysql\lib\debug
for debug versions.
For the complete usage of nmake, visit http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dv_vcce4/html/evgrfRunningNMAKE.asp.
If you are using the BitKeeper tree for compiling, All
Windows-specific Makefiles
are named as
Win_Makefile*
.
After the driver libraries are copied/installed to the system
directory, you can test whether the libraries are properly built
by using the samples provided in the
samples
subdirectory:
C:\>cd samples
C:\>nmake -f Makefile all
MySQL client libraries and include files from MySQL 4.0.0 or higher. (Preferably MySQL 4.0.16 or higher). This is required because MyODBC uses new calls and structures that exist only starting from this version of the library. To get the client libraries and include files, visit http://dev.mysql.com/downloads/.
The MySQL library must be configured with the
--enable-thread-safe-client
option.
libmysqlclient installed as a shared library.
One of the following Unix ODBC driver managers must be installed:
iodbc
3.0 or later
(http://www.iodbc.org)
unixodbc
Alpha 3 or later
(http://www.unixodbc.org)
If using a character set
that isn't compiled into the MySQL client library (the
defaults are: latin1 big5 czech euc_kr gb2312 gbk sjis
tis620 ujis) then you need to install the mysql character
definitions from the charsets
directory
into SHAREDIR
(by default,
/usr/local/mysql/share/mysql/charsets
).
These should be in place if you have installed the MySQL
server on the same machine.
Once you have all the required files, unpack the source files to a separate directory and follow the instructions as given below:
The configure script gives you a great deal of control over how you configure your MyODBC build. Typically you do this using options on the configure command line. You can also affect configure using certain environment variables. For a list of options and environment variables supported by configure, run this command:
shell> ./configure --help
Some of the more commonly used configure options are described here:
To compile MyODBC, you need to supply the MySQL client
include and library files path using the
--with-mysql-path=
option, where DIR
DIR
is the
directory where the MySQL is installed.
MySQL compile options can be determined by running
.
DIR
/bin/mysql_config
Supply the standard header and library files path for your
ODBC Driver Manager(iodbc
or
unixobc
).
If you are using iodbc
and
iodbc
is not installed in its default
location (/usr/local
), you might
have to use the
--with-iodbc=
option, where DIR
DIR
is the
directory where iodbc is installed.
If the iodbc headers do not reside in
,
you can use the
DIR
/include--with-iodbc-includes=
option to specify their location.
INCDIR
The applies to libraries. If they are not in
,
you can use the
DIR
/lib--with-iodbc-libs=
option.
LIBDIR
If you are using unixODBC
, use the
--with-unixODBC=
option (case sensitive) to make
configure look for
DIR
unixODBC
instead of
iodbc
by default,
DIR
is the directory where
unixODBC is installed.
If the unixODBC headers and libraries aren't located in
and
DIR
/include
,
use the
DIR
/lib--with-unixODBC-includes=
and
INCDIR
--with-unixODBC-libs=
options.
LIBDIR
You might want to specify an installation prefix other than
/usr/local
. For example, to install the
MyODBC drivers in /usr/local/odbc/lib
,
use the --prefix=/usr/local/odbc
option.
The final configuration command looks something like this:
shell>./configure --prefix=/usr/local \
--with-iodbc=/usr/local \
--with-mysql-path=/usr/local/mysql
In order to link the driver with MySQL thread safe client
libraries libmysqlclient_r.so
or
libmysqlclient_r.a
, you must specify the
following configure option:
--enable-thread-safe
and can be disabled(default) using
--disable-thread-safe
This option enables the building of driver thread-safe library
libmyodbc3_r.so
from by linking with mysql
thread-safe client library
libmysqlclient_r.so
(The extensions are OS
dependent).
In case while configuring with thread-safe option, and gotten
into a configure error; then look at the
config.log
and see whether it is due to the
lack of thread-libraries in the system; and supply one with LIBS
options i.e.
LIBS="-lpthread" ./configure ..
You can enable or disable the shared and static versions using these options:
--enable-shared[=yes/no] --disable-shared --enable-static[=yes/no] --disable-static
By default, all the binary distributions are built as
non-debugging versions (configured with
--without-debug
).
To enable debugging information, build the driver from source
distribution and use the --with-debug
) when you
run configure.
This option is available only for BK
clone
trees; not for normal source distributions.
By default, the driver is built with
(--without-docs
); And in case if you want the
documentation to be taken care in the normal build, then
configure with:
--with-docs
To build the driver libraries, you have to just execute make, which takes care of everything.
shell> make
If any errors occur, correct them and continue the build
process. If you aren't able to build, then send a detailed email
to <[email protected]>
for further assistance.
On most platforms, MySQL doesn't build or support
.so
(shared) client libraries by default,
because building with shared libraries has caused us problems in
the past.
In cases like this, you have to download the MySQL distribution and configure it with these options:
--without-server --enable-shared
To build shared driver libraries, you must specify the
--enable-shared
option for
configure. By default,
configure does not enable this option.
If you have configured with the
--disable-shared
option, you can build the
.so
file from the static libraries using
the following commands:
shell>cd MyODBC-3.51.01
shell>make
shell>cd driver
shell>CC=/usr/bin/gcc \
$CC -bundle -flat_namespace -undefined error \
-o .libs/libmyodbc3-3.51.01.so \
catalog.o connect.o cursor.o dll.o error.o execute.o \
handle.o info.o misc.o myodbc3.o options.o prepare.o \
results.o transact.o utility.o \
-L/usr/local/mysql/lib/mysql/ \
-L/usr/local/iodbc/lib/ \
-lz -lc -lmysqlclient -liodbcinst
Make sure to change -liodbcinst
to
-lodbcinst
if you are using unixODBC instead of
iODBC, and configure the library paths accordingly.
This builds and places the
libmyodbc3-3.51.01.so
file in the
.libs
directory. Copy this file to MyODBC
library directory (/usr/local/lib
(or the
lib
directory under the installation
directory that you supplied with the --prefix
).
shell>cd .libs
shell>cp libmyodbc3-3.51.01.so /usr/local/lib
shell>cd /usr/local/lib
shell>ln -s libmyodbc3-3.51.01.so libmyodbc3.so
To build the thread-safe driver library:
shell>CC=/usr/bin/gcc \
$CC -bundle -flat_namespace -undefined error
-o .libs/libmyodbc3_r-3.51.01.so catalog.o connect.o cursor.o dll.o error.o execute.o handle.o info.o misc.o myodbc3.o options.o prepare.o results.o transact.o utility.o -L/usr/local/mysql/lib/mysql/ -L/usr/local/iodbc/lib/ -lz -lc -lmysqlclient_r -liodbcinst
To install the driver libraries, execute the following command:
shell> make install
That command installs one of the following sets of libraries:
For MyODBC 3.51:
libmyodbc3.so
libmyodbc3-3.51.01.so
, where 3.51.01 is
the version of the driver
libmyodbc3.a
For thread-safe MyODBC 3.51:
libmyodbc3_r.so
libmyodbc3-3_r.51.01.so
libmyodbc3_r.a
For MyODBC 2.5.0:
libmyodbc.so
libmyodbc-2.50.39.so
, where 2.50.39 is
the version of the driver
libmyodbc.a
For more information on build process, refer to the
INSTALL
file that comes with the source
distribution. Note that if you are trying to use the
make from Sun, you may end up with errors. On
the other hand, GNU gmake should work fine on
all platforms.
To run the basic samples provided in the distribution with the libraries that you built, just execute:
shell> make test
Make sure the DSN 'myodbc3' is configured first in
odbc.ini
and environment variable
ODBCINI
is pointing to the right
odbc.ini
file; and MySQL server is running.
You can find a sample odbc.ini
with the
driver distribution.
You can even modify the samples/run-samples
script to pass the desired DSN, UID, and PASSWORD values as the
command line arguments to each sample.
To build the driver on Mac OS X (Darwin), make use of the following configure example:
shell> ./configure --prefix=/usr/local
--with-unixODBC=/usr/local
--with-mysql-path=/usr/local/mysql
--disable-shared
--enable-gui=no
--host=powerpc-apple
The command assumes that the unixODBC and MySQL are installed in the default locations. If not, configure accordingly.
On Mac OS X, --enable-shared
builds
.dylib
files by default. You can build
.so
files like this:
shell>make
shell>cd driver
shell>CC=/usr/bin/gcc \
$CC -bundle -flat_namespace -undefined error
-o .libs/libmyodbc3-3.51.01.so *.o -L/usr/local/mysql/lib/ -L/usr/local/iodbc/lib -liodbcinst -lmysqlclient -lz -lc
To build the thread-safe driver library:
shell>CC=/usr/bin/gcc \
$CC -bundle -flat_namespace -undefined error
-o .libs/libmyodbc3-3.51.01.so *.o -L/usr/local/mysql/lib/ -L/usr/local/iodbc/lib -liodbcinst -lmysqlclienti_r -lz -lc -lpthread
Make sure to change the -liodbcinst
to
-lodbcinst
in case of using unixODBC instead of
iODBC and configure the libraries path accordingly.
In Apple's version of GCC, both cc and gcc are actually symbolic links to gcc3.
Copy this library to the $prefix/lib
directory and symlink to libmyodbc3.so
.
You can cross-check the output shared-library properties using this command:
shell> otool -LD .libs/libmyodbc3-3.51.01.so
To build the driver on HP-UX 10.x or 11.x, make use of the following configure example:
If using cc:
shell>CC="cc" \
CFLAGS="+z" \
LDFLAGS="-Wl,+b:-Wl,+s" \
./configure --prefix=/usr/local
--with-unixodbc=/usr/local --with-mysql-path=/usr/local/mysql/lib/mysql --enable-shared --enable-thread-safe
If using gcc:
shell>CC="gcc" \
LDFLAGS="-Wl,+b:-Wl,+s" \
./configure --prefix=/usr/local
--with-unixodbc=/usr/local --with-mysql-path=/usr/local/mysql --enable-shared --enable-thread-safe
Once the driver is built, cross-check its attributes using
chatr .libs/libmyodbc3.sl to see whether or
not you need to have the MySQL client libraries path using the
SHLIB_PATH
environment variable. For static
versions, ignore all shared-library options and run
configure with the
--disable-shared
option.
To build the driver on AIX, make use of the following configure example:
shell> ./configure --prefix=/usr/local
--with-unixodbc=/usr/local
--with-mysql-path=/usr/local/mysql
--disable-shared
--enable-thread-safe
NOTE: For more information about how to build and set up the static and shared libraries across the different platforms refer to ' Using static and shared libraries across platforms'.
Note: You should read this section only if you are interested in helping us test our new code.
To obtain our most recent development source tree, use these instructions:
See Section 2.8.3, “Installing from the Development Source Tree”, for instructions on how to download and install BitKeeper.
After BitKeeper is installed, first go to the directory you want to work from, and then use this command if you want to clone the MyODBC 3.51 branch:
shell> bk clone bk://mysql.bkbits.net/myodbc3 myodbc-3.51
In the preceding example, the source tree is set up in the
myodbc-3.51/
or by default
myodbc3/
subdirectory of your current
directory. If you are behind the firewall and can only
initiate HTTP connections, you can also use BitKeeper via
HTTP. If you are required to use a proxy server, simply set
the environment variable http_proxy
to
point to your proxy:
shell> export http_proxy="http://your.proxy.server:8080/"
Replace the bk://
with
http://
when doing a clone. Example:
shell> bk clone http://mysql.bkbits.net/myodbc3 myodbc-3.51
The initial download of the source tree may take a while, depending on the speed of your connection; be patient.
You need GNU autoconf 2.52 (or newer), automake 1.4, libtool 1.4, and m4 to run the next set of commands.
shell>cd myodbc-3.51
shell>bk -r edit
shell>aclocal; autoheader; autoconf; automake;
shell>./configure # Add your favorite options here
shell>make
For more information on how to build, refer to
INSTALL
file located in the same
directory. On Windows, make use of Windows Makefiles
WIN-Makefile
and
WIN-Makefile_debug
in building the
driver, for more information, see
Section 26.1.6, “Installing MyODBC from a Source Distribution on Windows”.
When the build is done, run make install to install the MyODBC 3.51 driver on your system.
If you have gotten to the make stage and
the distribution does not compile, please report it to
<[email protected]>
.
After the initial bk clone operation to get the source tree, you should run bk pull periodically to get the updates.
You can examine the change history for the tree with all the
diffs by using bk sccstool. If you see some
funny diffs or code that you have a question about, do not
hesitate to send email message to
<[email protected]>
.
Also, if you think you have a better idea on how to do something, send an email message to the same address with a patch. bk diffs produces a patch for you after you have made changes to the source. If you do not have the time to code your idea, just send a description.
BitKeeper has a help utility that you can access via bk helptool.
You can also browse changesets, comments and source code online by browsing to http://mysql.bkbits.net:8080/myodbc3.
This section describes how to configure MyODBC, including DSN creation and the different arguments that the driver takes as an input arguments in the connection string. It also describes how to create an ODBC trace file.
A "data source" is a place where data comes from. The data source must have a persistent identifier, the Data Source Name. Using the Data Source Name, MySQL can access initialization information. With the initialization information, MySQL knows where to access the database and what settings to use when the access starts.
In effect, the data source is the path to the data. In different contexts this might mean different things, but typically it identifies a running MySQL server (for example via a network address or service name), plus the default database for that server at connection time, plus necessary connection information such as the port. The MySQL drivers (and, on Windows systems, the ODBC Driver Manager) use the data source for connecting. An administrative utility called the Microsoft ODBC Data Source Administrator may be useful for this purpose.
There are two places where the initialization information might be: in the Windows registry (on a Windows system), or in a DSN file (on any system).
If the information is in the Windows registry, it is called a "Machine data source". It might be a "User data source", in which case only one user can see it. Or it might be a "System data source" in which case it is accessible to all users on the computer, or indeed to all users connected to the computer, if the users are connected by Microsoft Windows NT services. When you run the ODBC Data Administration program, you have a choice whether to use "User" or "System" -- there are separate tabs.
If the information is in a DSN file, it is called a "File data source". This is a text file. Its advantages are: (a) it is an option for any kind of computer, not just a computer with a Windows operating system; (b) its contents can be transmitted or copied relatively easily.
To add and configure a new MyODBC data source on Windows, use
the ODBC Data Source Administrator
. The
ODBC Administrator
updates your data source
connection information. As you add data sources, the
ODBC Administrator
updates the registry
information for you.
To open the ODBC Administrator
from the
Control Panel:
Click Start
, point to
Settings
, and then click Control
Panel
.
On computers running Microsoft Windows 2000 or newer,
double-click Administrative Tools
, and
then double-click Data Sources (ODBC)
. On
computers running older versions of Windows, double-click
32-bit ODBC
or ODBC
.
The ODBC Data Source Administrator
dialog
box appears, as shown here:
Click Help
for detailed information about
each tab of the ODBC Data Source
Administrator
dialog box.
To add a data source on Windows:
Open the ODBC Data Source Administrator
.
In the ODBC Data Source Administrator
dialog box, click Add
. The
Create New Data Source
dialog box
appears.
Select MySQL ODBC 3.51 Driver
, and then
click Finish
. The MySQL ODBC
3.51 Driver - DSN Configuration
dialog box
appears, as shown here:
In the Data Source Name
box, enter the
name of the data source you want to access. It can be any
valid name that you choose.
In the Description
box, enter the
description needed for the DSN.
For Host or Server Name (or IP)
box,
enter the name of the MySQL server host that you want to
access. By default, it is localhost
.
In the Database Name
box, enter the name
of the MySQL database that you want to use as the default
database.
In the User
box, enter your MySQL
username (your database user ID).
In the Password
box, enter your password.
In the Port
box, enter the port number if
it is not the default (3306).
In the SQL Command
box, you can enter an
optional SQL statement that you want to issue automatically
after the connection has been established.
The final dialog looks like this:
Click OK
to add this data source.
Note: Upon clicking
OK
, the Data Sources
dialog box appears, and the ODBC
Administrator
updates the registry information. The
username and connect string that you entered become the default
connection values for this data source when you connect to it.
You can also test whether your settings are suitable for
connecting to the server using the button Test Data
Source
. This feature is available only for the MyODBC
3.51 driver. A successful test results in the following window:
A failed test results in an error:
The DSN configuration dialog also has an
Options
button. If you select it, the
following options dialog appears displaying that control driver
behavior. Refer to Section 26.1.9.4, “Connection Parameters”, for
information about the meaning of these options.
Note: The options listed under
Driver Trace Options
are disabled (grayed
out) unless you are using the debugging version of the driver
DLL.
To modify a data source on Windows:
Open the ODBC Data Source Administrator
.
Click the appropriate DSN tab.
Select the MySQL data source that you want to modify and
then click Configure
. The MySQL
ODBC 3.51 Driver - DSN Configuration
dialog box
appears.
Modify the applicable data source fields, and then click
OK
.
When you have finished modifying the information in this dialog
box, the ODBC Administrator
updates the
registry information.
On Unix
, you configure DSN entries directly
in the odbc.ini
file. Here is a typical
odbc.ini
file that configures
myodbc
and myodbc3
as the
DSN names for MyODBC 2.50 and MyODBC 3.51, respectively:
; ; odbc.ini configuration for MyODBC and MyODBC 3.51 drivers ; [ODBC Data Sources] myodbc = MyODBC 2.50 Driver DSN myodbc3 = MyODBC 3.51 Driver DSN [myodbc] Driver = /usr/local/lib/libmyodbc.so Description = MyODBC 2.50 Driver DSN SERVER = localhost PORT = USER = root Password = Database = test OPTION = 3 SOCKET = [myodbc3] Driver = /usr/local/lib/libmyodbc3.so Description = MyODBC 3.51 Driver DSN SERVER = localhost PORT = USER = root Password = Database = test OPTION = 3 SOCKET = [Default] Driver = /usr/local/lib/libmyodbc3.so Description = MyODBC 3.51 Driver DSN SERVER = localhost PORT = USER = root Password = Database = test OPTION = 3 SOCKET =
Refer to the Section 26.1.9.4, “Connection Parameters”, for the list of connection parameters that can be supplied.
Note: If you are using unixODBC, you can use the following tools in order to set up the DSN:
ODBCConfig GUI tool(HOWTO: ODBCConfig)
odbcinst
In some cases when using unixODBC, you might get this error:
Data source name not found and no default driver specified
If this happens, make sure the ODBCINI
and
ODBCSYSINI
environment variables are pointing
to the right odbc.ini
file. For example, if
your odbc.ini
file is located in
/usr/local/etc
, set the environment
variables like this:
export ODBCINI=/usr/local/etc/odbc.ini export ODBCSYSINI=/usr/local/etc
You can specify the following parameters for MyODBC in the
[Data Source Name]
section of an
ODBC.INI
file or through the
InConnectionString
argument in the
SQLDriverConnect()
call.
Parameter | Default Value | Comment |
user | ODBC (on Windows) | The username used to connect to MySQL. |
server | localhost | The hostname of the MySQL server. |
database | The default database. | |
option | 0 | Options that specify how MyODBC should work. See below. |
port | 3306 | The TCP/IP port to use if server is not
localhost . |
stmt | A statement to execute when connecting to MySQL. | |
password | The password for the user account on
server . | |
socket | The Unix socket file or Windows named pipe to connect to if
server is
localhost . |
The option
argument is used to tell MyODBC
that the client isn't 100% ODBC compliant. On Windows, you
normally select options by toggling the checkboxes in the
connection screen, but you can also select them in the
option
argument. The following options are
listed in the order in which they appear in the MyODBC connect
screen:
Value | Description |
1 | The client can't handle that MyODBC returns the real width of a column. |
2 | The client can't handle that MySQL returns the true value of affected rows. If this flag is set, MySQL returns “found rows” instead. You must have MySQL 3.21.14 or newer to get this to work. |
4 | Make a debug log in c:\myodbc.log . This is the same
as putting
MYSQL_DEBUG=d:t:O,c::\myodbc.log in
AUTOEXEC.BAT . (On Unix, the file is
/tmp/myodbc.log .) |
8 | Don't set any packet limit for results and parameters. |
16 | Don't prompt for questions even if driver would like to prompt. |
32 | Enable or disable the dynamic cursor support. (Not allowed in MyODBC 2.50.) |
64 | Ignore use of database name in
db_name.tbl_name.col_name . |
128 | Force use of ODBC manager cursors (experimental). |
256 | Disable the use of extended fetch (experimental). |
512 | Pad CHAR columns to full column length. |
1024 | SQLDescribeCol() returns fully qualified column
names. |
2048 | Use the compressed client/server protocol. |
4096 | Tell server to ignore space after function name and before
‘( ’ (needed by
PowerBuilder). This makes all function names keywords. |
8192 | Connect with named pipes to a mysqld server running on NT. |
16384 | Change LONGLONG columns to INT
columns (some applications can't handle
LONGLONG ). |
32768 | Return 'user' as Table_qualifier and
Table_owner from
SQLTables (experimental). |
65536 | Read parameters from the [client] and
[odbc] groups from
my.cnf . |
131072 | Add some extra safety checks (should not be needed but...). |
262144 | Disable transactions. |
524288 | Enable query logging to
c:\myodbc.sql (/tmp/myodbc.sql )
file. (Enabled only in debug mode.) |
1048576 | Do not cache the results locally in the driver, instead read from server
(mysql_use_result() ). This works only
for forward-only cursors. This option is very important
in dealing with large tables when you don't want the
driver to cache the entire result set. |
2097152 | Force the use of Forward-only cursor type. In case of
applications setting the default static/dynamic cursor
type, and one wants the driver to use non-cache result
sets, then this option ensures the forward-only cursor
behavior. |
To select multiple options, add together their values. For
example, setting option
to 12 (4+8) gives you
debugging without packet limits.
The default myodbc3.dll
is compiled for
optimal performance. If you want to debug MyODBC 3.51 (for
example, to enable tracing), you should instead use
myodbc3d.dll
. To install this file, copy
myodbc3d.dll
over the installed
myodbc3.dll
file. Make sure to revert back
to the release version of the driver DLL once you are done with
the debugging because the debug version may cause performance
issues. Note that the myodbc3d.dll
isn't
included in MyODBC 3.51.07 through 3.51.11. If you are using one
of these versions, you should copy that DLL from a previous
version (for example, 3.51.06).
For MyODBC 2.50, myodbc.dll
and
myodbcd.dll
are used instead.
The following table shows some recommended
option
values for various configurations:
Configuration | Option Value |
Microsoft Access | 3 |
Microsoft Visual Basic | 3 |
Large tables with too many rows | 2049 |
Driver trace generation (Debug mode) | 4 |
Query log generation (Debug mode) | 524288 |
Generate driver trace as well as query log (Debug mode) | 524292 |
Large tables with no-cache results | 3145731 |
Yes. You can connect to the MySQL server using SQLDriverConnect,
by specifying the DRIVER
name field. Here are
the connection strings for MyODBC using DSN-Less connection:
For MyODBC 2.50:
ConnectionString = "DRIVER={MySQL};\ SERVER=localhost;\ DATABASE=test;\ USER=venu;\ PASSWORD=venu;\ OPTION=3;"
For MyODBC 3.51:
ConnectionString = "DRIVER={MySQL ODBC 3.51 Driver};\ SERVER=localhost;\ DATABASE=test;\ USER=venu;\ PASSWORD=venu;\ OPTION=3;"
If your programming language converts backslash followed by whitespace to a space, it is preferable to specify the connection string as a single long string, or to use a concatenation of multiple strings that does not add spaces in between. For example:
ConnectionString = "DRIVER={MySQL ODBC 3.51 Driver};" "SERVER=localhost;" "DATABASE=test;" "USER=venu;" "PASSWORD=venu;" "OPTION=3;"
Refer to the Section 26.1.9.4, “Connection Parameters”, for the list of connection parameters that can be supplied.
If you want to connect to system A from system B with a username
and password of myuser
and
mypassword
, here is a simple procedure.
On system A, follow these steps:
Start the MySQL server.
Use GRANT
to set up an account with a
username of myuser
that can connect from
system B using a password of myuser
:
GRANT ALL ON *.* to 'myuser'@'B' IDENTIFIED BY 'mypassword';
The GRANT
statement grants all privileges
to user myuser
for connecting from
system B using the password mypassword
.
To execute this statement, you should be either
root
on system A (or another user who has
appropriate privileges). For more information about MySQL
privileges, refer to
Section 5.8, “MySQL User Account Management”.
On system B, follow these steps:
Configure a MyODBC DSN using the following connection parameters:
DSN = remote_test SERVER or HOST = A (or IP address of system A) DATABASE = test (The default database or an appropriate one) USER = myuser PASSWORD = mypassword
To set up a DSN-less connection, refer to Section 26.1.9.5, “Connecting Without a Predefined DSN”.
Check whether you are able to access system A from system B by using ping or other means. If you are not able to reach system A, check your network or Internet connections or contact your system administrator.
Try to connect using DSN=remote_test
. If
it fails, trace the MyODBC log, and take the further steps
based on the error message from the log. If you need further
assistance, send a detailed mail message to
<[email protected]>
.
You can also find a simple HOWTO at http://www.phphelp.com/tutorial/using-myodbc-to-connect-to-a-remote-database.html.
If you encounter difficulties or problems with MyODBC, you
should start by making a log file from the ODBC
Manager
(the log you get when requesting logs from
ODBC ADMIN
) and MyODBC.
To get an ODBC trace through Driver Manager, do the following:
Open ODBC Data source administrator:
Click Start
, point to
Settings
, and then click
Control Panel
.
On computers running Microsoft Windows 2000, XP, or
2003, double-click Administrative
Tools
, and then double-click Data
Sources (ODBC)
, as shown below.
On computers running an earlier version of Microsoft
Windows, double-click 32-bit ODBC
or
ODBC
in the Control Panel.
The ODBC Data Source Administrator
dialog box appears, as shown below:
Click Help for detailed information about each tab of the ODBC Data Source Administrator dialog box.
Enable the trace option. The procedure for this differs for Windows and Unix.
To enable the trace option on Windows:
The Tracing
tab of the ODBC Data
Source Administrator dialog box enables you to configure
the way ODBC function calls are traced.
When you activate tracing from the
Tracing
tab, the Driver
Manager
logs all ODBC function calls for all
subsequently run applications.
ODBC function calls from applications running before tracing is activated are not logged. ODBC function calls are recorded in a log file you specify.
Tracing ceases only after you click Stop
Tracing Now
. Remember that while tracing is
on, the log file continues to increase in size and that
tracing affects the performance of all your ODBC
applications.
To enable the trace option on Unix:
On Unix, you need to explicitly set the
Trace
option in the
ODBC.INI
file.
Set the tracing ON
or
OFF
by using
TraceFile
and
Trace
parameters in
odbc.ini
as shown below:
TraceFile = /tmp/odbc.trace Trace = 1
TraceFile
specifies the name and full
path of the trace file and Trace
is
set to ON
or OFF
.
You can also use 1
or
YES
for ON
and
0
or NO
for
OFF
. If you are using
ODBCConfig from
unixODBC
, then follow the
instructions for tracing unixODBC
calls at
HOWTO-ODBCConfig.
To generate a MyODBC log, do the following:
Ensure that you are using the driver debug DLL (that is,
myodbc3d.dll
and not
myodbc3.dll
for MyODBC 3.51, and
myodbcd.dll
for MyODBC 2.50).
The easiest way to do this is to get
myodbc3d.dll
(or
myodbcd.dll
) from the MyODBC 3.51
distribution and copy it over the
myodbc3.dll
(or
myodbc.dll
), which is probably in
your C:\windows\system32
or
C:\winnt\system32
directory. Note
that you probably want to restore the old
myodbc.dll
file when you have
finished testing, as this is a lot faster than
myodbc3d.dll
(or
myodbcd.dll
), so do keep a backup
copy of original DLLs.
Enable the Trace MyODBC
option flag
in the MyODBC connect/configure screen. The log is
written to file C:\myodbc.log
. If
the trace option is not remembered when you are going
back to the above screen, it means that you are not
using the myodbcd.dll
driver (see
above). On Linux or if you are using DSN-Less
connection, then you need to supply
OPTION=4
in the connection string.
Start your application and try to get it to fail. Then check the MyODBC trace file to find out what could be wrong.
If you find out something is wrong, please send a mail
message to <[email protected]>
(or to
<[email protected]>
if you have a support
contract from MySQL AB) with a brief description of the
problem, with the following additional information:
MyODBC version
ODBC Driver Manager type and version
MySQL server version
ODBC trace from Driver Manager
MyODBC log file from MyODBC driver
Simple reproducible sample
Remember that the more information you can supply to us, the more likely it is that we can fix the problem!
Also, before posting the bug, check the MyODBC mailing list archive at http://lists.mysql.com/.
MyODBC has been tested with the following applications:
MS Access 95, 97, 2000, and 2002
C++-Builder, Borland Builder 4
Centura Team Developer (formerly Gupta SQL/Windows)
ColdFusion (on Solaris and NT with service pack 5), How-to: MySQL and Coldfusion. Troubleshooting Data Sources and Database Connectivity for UnixPlatforms.
Crystal Reports
DataJunction
Delphi
ERwin
MS Excel
iHTML
FileMaker Pro
FoxPro
Notes 4.5/4.6
MS Visio Enterprise 2000
Vision
Visual Objects
Visual Interdev
SBSS
Perl DBD-ODBC
Paradox
Powerbuilder
Powerdesigner 32-bit
MS Visual C++
Visual Basic
ODBC.NET through CSharp(C#), VB and C++
Data Architect(http://thekompany.com/products/dataarchitect/)
SQLExpress for Xbase++(http://www.SQLExpress.net)
Open Office (http://www.openoffice.org) How-to: MySQL + OpenOffice. How-to: OpenOffice + MyODBC + unixODBC.
Star Office (http://wwws.sun.com/software/star/staroffice/6.0/index.html)
G2-ODBC bridge (http://www.gensym.com)
Sambar Server (http://www.sambarserver.info) How-to: MyODBC + SambarServer + MySQL.
If you know of any other applications that work with MyODBC,
please send mail to <[email protected]>
about
them.
Most programs should work with MyODBC, but for each of those listed here, we have tested it ourselves or received confirmation from some user that it works. Many of the descriptions provide workarounds for problems that you might encounter.
Program
Comment
To make Access work:
If you are using Access 2000, you should get and install
the newest (version 2.6 or higher) Microsoft MDAC
(Microsoft Data Access Components
)
from http://www.microsoft.com/data/. This
fixes a bug in Access that when you export data to
MySQL, the table and column names aren't specified.
Another way to work around this bug is to upgrade to
MyODBC 2.50.33 and MySQL 3.23.x, which together provide
a workaround for the problem.
You should also get and apply the Microsoft Jet 4.0
Service Pack 5 (SP5) which can be found at
http://support.microsoft.com/default.aspx?scid=kb;EN-US;q239114.
This fixes some cases where columns are marked as
#DELETED#
in Access.
Note: If you are using MySQL 3.22, you must to apply the MDAC patch and use MyODBC 2.50.32 or 2.50.34 and up to work around this problem.
For all versions of Access, you should enable the MyODBC
Return matching rows
option. For
Access 2.0, you should additionally enable the
Simulate ODBC 1.0
option.
You should have a timestamp in all tables that you want
to be able to update. For maximum portability, don't use
a length specification in the column declaration. That
is, use TIMESTAMP
, not
TIMESTAMP(
,
n
)n
< 14.
You should have a primary key in the table. If not, new
or updated rows may show up as
#DELETED#
.
Use only DOUBLE
float fields. Access
fails when comparing with single floats. The symptom
usually is that new or updated rows may show up as
#DELETED#
or that you can't find or
update rows.
If you are using MyODBC to link to a table that has a
BIGINT
column, the results are
displayed as #DELETED
. The work
around solution is:
Have one more dummy column with
TIMESTAMP
as the data type.
Select the Change BIGINT columns to
INT
option in the connection dialog in
ODBC DSN Administrator.
Delete the table link from Access and re-create it.
Old records still display as
#DELETED#
, but newly added/updated
records are displayed properly.
If you still get the error Another user has
changed your data
after adding a
TIMESTAMP
column, the following trick
may help you:
Don't use a table
data sheet view.
Instead, create a form with the fields you want, and use
that form
data sheet view. You should
set the DefaultValue
property for the
TIMESTAMP
column to
NOW()
. It may be a good idea to hide
the TIMESTAMP
column from view so
your users are not confused.
In some cases, Access may generate illegal SQL
statements that MySQL can't understand. You can fix this
by selecting
"Query|SQLSpecific|Pass-Through"
from
the Access menu.
On NT, Access reports BLOB
columns as
OLE OBJECTS
. If you want to have
MEMO
columns instead, you should
change BLOB
columns to
TEXT
with ALTER
TABLE
.
Access can't always handle DATE
columns properly. If you have a problem with these,
change the columns to DATETIME
.
If you have in Access a column defined as
BYTE
, Access tries to export this as
TINYINT
instead of TINYINT
UNSIGNED
. This gives you problems if you have
values larger than 127 in the column.
When you are coding with the ADO API and MyODBC, you need to
pay attention to some default properties that aren't
supported by the MySQL server. For example, using the
CursorLocation Property
as
adUseServer
returns a result of -1 for
the RecordCount Property
. To have the
right value, you need to set this property to
adUseClient
, as shown in the VB code
here:
Dim myconn As New ADODB.Connection Dim myrs As New Recordset Dim mySQL As String Dim myrows As Long myconn.Open "DSN=MyODBCsample" mySQL = "SELECT * from user" myrs.Source = mySQL Set myrs.ActiveConnection = myconn myrs.CursorLocation = adUseClient myrs.Open myrows = myrs.RecordCount myrs.Close myconn.Close
Another workaround is to use a SELECT
COUNT(*)
statement for a similar query to get the
correct row count.
Active server pages (ASP)
You should select the Return matching
rows
option.
BDE applications
To get these to work, you should select the Don't
optimize column widths
and Return
matching rows
options.
When you start a query, you can use the
Active
property or the
Open
method. Note that
Active
starts by automatically issuing a
SELECT * FROM ...
query. That may not be
a good thing if your tables are large.
The following information is taken from the ColdFusion documentation:
Use the following information to configure ColdFusion Server for Linux to use the unixODBC driver with MyODBC for MySQL data sources. Allaire has verified that MyODBC 2.50.26 works with MySQL 3.22.27 and ColdFusion for Linux. (Any newer version should also work.) You can download MyODBC at http://dev.mysql.com/downloads/connector/odbc/.
ColdFusion version 4.5.1 allows you to us the ColdFusion
Administrator to add the MySQL data source. However, the
driver is not included with ColdFusion version 4.5.1. Before
the MySQL driver appears in the ODBC datasources drop-down
list, you must build and copy the MyODBC driver to
/opt/coldfusion/lib/libmyodbc.so
.
The Contrib directory contains the program
mydsn-
which allows you to build and remove the DSN registry file
for the MyODBC driver on Coldfusion applications.
xxx
.zip
You have to change it to output VARCHAR
rather than ENUM
, as it exports the
latter in a manner that causes MySQL problems.
Works. A few tips:
If you have problems with dates, try to select them as
strings using the CONCAT()
function.
For example:
SELECT CONCAT(rise_time), CONCAT(set_time) FROM sunrise_sunset;
Values retrieved as strings this way should be correctly recognized as time values by Excel97.
The purpose of CONCAT()
in this
example is to fool ODBC into thinking the column is of
“string type.” Without the
CONCAT()
, ODBC knows the column is of
time type, and Excel does not understand that.
Note that this is a bug in Excel, because it automatically converts a string to a time. This would be great if the source was a text file, but is unfortunate when the source is an ODBC connection that reports exact types for each column.
To retrieve data from MySQL to Word/Excel documents, you need to use the MyODBC driver and the Add-in Microsoft Query help.
For example, create a database with a table containing two columns of text:
Insert rows using the mysql client command-line tool.
Create a DSN file using the ODBC manager, for example,
my
for the database that was just
created.
Open the Word application.
Create a blank new document.
In the Database
tool bar, press the
Insert Database
button.
Press the Get Data
button.
At the right hand of the Get Data
screen, press the Ms Query
button.
In Ms Query
, create a new data source
using the my
DSN file.
Select the new query.
Select the columns that you want.
Make a filter if you want.
Make a Sort if you want.
Select Return Data to Microsoft Word
.
Click Finish
.
Click Insert Data
and select the
records.
Click OK
and you see the rows in your
Word document.
Test program for ODBC.
You must use BDE 3.2 or newer. Select the Don't
optimize column width
option when connecting to
MySQL.
Also, here is some potentially useful Delphi code that sets
up both an ODBC entry and a BDE entry for MyODBC. The BDE
entry requires a BDE Alias Editor that is free at a Delphi
Super Page near you. (Thanks to Bryan Brunton
<[email protected]>
for this):
fReg:= TRegistry.Create; fReg.OpenKey('\Software\ODBC\ODBC.INI\DocumentsFab', True); fReg.WriteString('Database', 'Documents'); fReg.WriteString('Description', ' '); fReg.WriteString('Driver', 'C:\WINNT\System32\myodbc.dll'); fReg.WriteString('Flag', '1'); fReg.WriteString('Password', ''); fReg.WriteString('Port', ' '); fReg.WriteString('Server', 'xmark'); fReg.WriteString('User', 'winuser'); fReg.OpenKey('\Software\ODBC\ODBC.INI\ODBC Data Sources', True); fReg.WriteString('DocumentsFab', 'MySQL'); fReg.CloseKey; fReg.Free; Memo1.Lines.Add('DATABASE NAME='); Memo1.Lines.Add('USER NAME='); Memo1.Lines.Add('ODBC DSN=DocumentsFab'); Memo1.Lines.Add('OPEN MODE=READ/WRITE'); Memo1.Lines.Add('BATCH COUNT=200'); Memo1.Lines.Add('LANGDRIVER='); Memo1.Lines.Add('MAX ROWS=-1'); Memo1.Lines.Add('SCHEMA CACHE DIR='); Memo1.Lines.Add('SCHEMA CACHE SIZE=8'); Memo1.Lines.Add('SCHEMA CACHE TIME=-1'); Memo1.Lines.Add('SQLPASSTHRU MODE=SHARED AUTOCOMMIT'); Memo1.Lines.Add('SQLQRYMODE='); Memo1.Lines.Add('ENABLE SCHEMA CACHE=FALSE'); Memo1.Lines.Add('ENABLE BCD=FALSE'); Memo1.Lines.Add('ROWSET SIZE=20'); Memo1.Lines.Add('BLOBS TO CACHE=64'); Memo1.Lines.Add('BLOB SIZE=32'); AliasEditor.Add('DocumentsFab','MySQL',Memo1.Lines);
Tested with BDE 3.0. The only known problem is that when the
table schema changes, query fields are not updated. BDE,
however, does not seem to recognize primary keys, only the
index named PRIMARY
, though this has not
been a problem.
Vision
You should select the Return matching
rows
option.
To be able to update a table, you must define a primary key for the table.
Visual Basic with ADO can't handle big integers. This means
that some queries like SHOW PROCESSLIST
do not work properly. The fix is to use
OPTION=16384
in the ODBC connect string
or to select the Change BIGINT columns to
INT
option in the MyODBC connect screen. You may
also want to select the Return matching
rows
option.
VisualInterDev
If you have a BIGINT
in your result, you
may get the error [Microsoft][ODBC Driver Manager]
Driver does not support this parameter
Try
selecting the Change BIGINT columns to
INT
option in the MyODBC connect screen.
Visual Objects
You should select the Don't optimize column
widths
option.
MS Visio Enterprise 2000
We made database model diagram by connecting from MS Vision Enterprise 2000 to MySQL via MyODBC (2.50.37 or greater) and using Visio's reverse engineer function to retrieve information about the DB (Visio shows all the column definitions, primary keys, Indexes and so on). Also we tested by designing new tables in Visio and exported them to MySQL via MyODBC.
This section answers MyODBC connection-related questions.
For more information, refer to
MS
KnowledgeBase Article(Q260558). Also, make sure you have
the latest valid ctl3d32.dll
in your system
directory.
Refer to this document about connection pooling: http://support.microsoft.com/default.aspx?scid=kb;EN-US;q169470.
#DELETED#
Another user has modified the record that you have modified
While Editing RecordsThis section of the document answers questions related to MyODBC with Microsoft Access.
The following must be done on your client PC in order to make Microsoft Access work with MyODBC.
If you are using Access 2000, you should get and install the
newest (version 2.6 or higher) Microsoft MDAC
(Microsoft Data Access Components
) from
http://www.microsoft.com/data/. This fixes a
bug in Access that when you export data to MySQL, the table
and column names aren't specified. Another way to work
around this bug is to upgrade to MyODBC 2.50.33 and MySQL
3.23.x, which together provide a workaround for the problem.
You should also get and apply the Microsoft Jet 4.0 Service
Pack 5 (SP5) which can be found at
http://support.microsoft.com/default.aspx?scid=kb;EN-US;q239114.
This fixes some cases where columns are marked as
#DELETED#
in Access.
Note: If you are using MySQL 3.22, you must to apply the MDAC patch and use MyODBC 2.50.32 or 2.50.34 and up to work around this problem.
Install the latest version of MySQL from http://dev.mysql.com/downloads/.
Install the latest version of MyODBC 3.51 or 2.50 from http://dev.mysql.com/downloads/connector/odbc/.
For all Access versions, you should enable the
Return matching rows
option.
Start working with Access as the front end for MySQL Server through MyODBC.
You cannot export a table or query to MySQL unless you have installed MyODBC.
To export a table from Access to MySQL, follow these instructions:
When you open an Access database or an Access project, a Database window appears. It displays shortcuts for creating new database objects and opening existing objects.
Click the name of the table
or
query
you want to export, and then in the
File
menu, select
Export
.
In the Export Object Type
dialog box, in the
Object
name
ToSave As Type
box, select ODBC
Databases ()
as shown here:
In the Export
dialog box, enter a name
for the file (or use the suggested name), and then select
OK
.
The Select Data Source dialog box is displayed; it lists the defined data sources for any ODBC drivers installed on your computer. Click either the File Data Source or Machine Data Source tab, and then double-click the MyODBC or MyODBC 3.51 data source that you want to export to. To define a new data source for MyODBC, please Section 26.1.9.2, “Configuring a MyODBC DSN on Windows”.
Microsoft Access connects to the MySQL Server through this data source and exports new tables and or data.
You cannot export a table or query to MySQL database unless you have installed the MyODBC.
To import or link a table or tables from MySQL to Access, follow the instructions:
Open a database, or switch to the Database window for the open database.
To import tables, on the File
menu, point
to Get External Data
, and then click
Import
. To link tables, on the File menu,
point to Get External Data
, and then
click Link Tables
.
In the Import
(or
Link
) dialog box, in the Files Of Type
box, select ODBC Databases ()
. The Select
Data Source dialog box lists the defined data sources The
Select Data Source dialog box is displayed; it lists the
defined data sources for any ODBC drivers installed on your
computer. Click either the File Data Source or Machine Data
Source tab, and then double-click the MyODBC or MyODBC 3.51
data source that you want to export to. To define a new data
source for the MyODBC or MyODBC 3.51 driver, please
Section 26.1.9.2, “Configuring a MyODBC DSN on Windows”.
If the ODBC data source that you selected requires you to
log on, enter your login ID and password (additional
information might also be required), and then click
OK
.
Microsoft Access connects to the MySQL server through
ODBC data source
and displays the list
of tables that you can import
or
link
.
Click each table that you want to import
or link
, and then click
OK
. If you're linking a table and it
doesn't have an index that uniquely identifies each record,
Microsoft Access displays a list of the fields in the linked
table. Click a field or a combination of fields that
uniquely identifies each record, and then click
OK
.
Yes. Use the following procedure to view or to refresh links when the structure or location of a linked table has changed. The Linked Table Manager lists the paths to all currently linked tables.
To view or refresh links:
Open the database that contains links to tables.
On the Tools
menu, point to
Add-ins
(Database
Utilities
in Access 2000 or newer), and then click
Linked Table Manager
.
Select the check box for the tables whose links you want to refresh.
Click OK to refresh the links.
Microsoft Access confirms a successful refresh or, if the table
wasn't found, displays the Select New Location
of
<table name> dialog box in which you can
specify its the table's new location.If several selected tables
have moved to the new location that you specify, the Linked
Table Manager searches that location for all selected tables,
and updates all links in one step.
To change the path for a set of linked tables:
Open the database that contains links to tables.
On the Tools
menu, point to
Add-ins
(Database
Utilities
in Access 2000 or newer), and then click
Linked Table Manager
.
Select the Always Prompt For A New
Location
check box.
Select the check box for the tables whose links you want to
change, and then click OK
.
In the Select New Location of
<table
name> dialog box, specify the new location, click
Open
, and then click
OK
.
If the inserted or updated records are shown as
#DELETED#
in the access, then:
If you are using Access 2000, you should get and install the
newest (version 2.6 or higher) Microsoft MDAC
(Microsoft Data Access Components
) from
http://www.microsoft.com/data/. This fixes a
bug in Access that when you export data to MySQL, the table
and column names aren't specified. Another way to work
around this bug is to upgrade to MyODBC 2.50.33 and MySQL
3.23.x, which together provide a workaround for the problem.
You should also get and apply the Microsoft Jet 4.0 Service
Pack 5 (SP5) which can be found at
http://support.microsoft.com/default.aspx?scid=kb;EN-US;q239114.
This fixes some cases where columns are marked as
#DELETED#
in Access.
Note: If you are using MySQL 3.22, you must to apply the MDAC patch and use MyODBC 2.50.32 or 2.50.34 and up to work around this problem.
For all versions of Access, you should enable the MyODBC
Return matching rows
option. For Access
2.0, you should additionally enable the Simulate
ODBC 1.0
option.
You should have a timestamp in all tables that you want to
be able to update. For maximum portability, don't use a
length specification in the column declaration. That is, use
TIMESTAMP
, not
TIMESTAMP(
,
n
)n
< 14.
You should have a primary key in the table. If not, new or
updated rows may show up as #DELETED#
.
Use only DOUBLE
float fields. Access
fails when comparing with single floats. The symptom usually
is that new or updated rows may show up as
#DELETED#
or that you can't find or
update rows.
If you are using MyODBC to link to a table that has a
BIGINT
column, the results are displayed
as #DELETED
. The work around solution is:
Have one more dummy column with
TIMESTAMP
as the data type.
Select the Change BIGINT columns to
INT
option in the connection dialog in ODBC
DSN Administrator.
Delete the table link from Access and re-create it.
Old records still display as #DELETED#
,
but newly added/updated records are displayed properly.
If you see the following errors, select the Return
Matching Rows
option in the DSN configuration dialog,
or specify OPTION=2
, as the connection
parameter:
Write Conflict. Another user has changed your data. Row cannot be located for updating. Some values may have been changed since it was last read.
This is a strange issue from Access 97, and doesn't appear with Access 2000 or 2002. You can overcome this by upgrading the MyODBC driver to at least MyODBC 3.51.02.
With some programs, this error may occur: Another user
has modified the record that you have modified
. In
most cases, this can be solved by doing one of the following
things:
Add a primary key for the table if one doesn't exist.
Add a timestamp column if one doesn't exist.
Only use double float fields. Some programs may fail when they compare single floats.
If these strategies don't help, you should start by making a log file from the ODBC manager (the log you get when requesting logs from ODBCADMIN) and a MyODBC log to help you figure out why things go wrong. For instructions, see Section 26.1.9.7, “Getting an ODBC Trace File”.
Read “How to Trap ODBC Login Error Messages in Access” at http://support.microsoft.com/support/kb/articles/Q124/9/01.asp?LN=EN-US&SD=gn&FR=0%3CP%3E.
If you have very large (long) tables in Access, it might take a
very long time to open them. Or you might run low on virtual
memory and eventually get an ODBC Query
Failed
error and the table cannot open. To deal with
this, select the following options:
Return Matching Rows (2)
Allow BIG Results (8).
These add up to a value of 10 (OPTION=10
).
Read “Set the QueryTimeout Value for ODBC Connections” at http://support.microsoft.com/default.aspx?scid=kb%3Ben-us%3B153756.
Refer to converters section for list of available tools.
SELECT COUNT(*) FROM tbl_name
Return an Error?AppendChunk()
or GetChunk()
ADO Methods, I Get an Error Multiple-step operation generated errors. Check each status value
.This section answers questions related to using MyODBC with Microsoft Visual Basic(ADO, DAO & RDO) and ASP.
It's because the COUNT(*)
expression is
returning a BIGINT
, and ADO can't make sense
of a number this big. Select the Change BIGINT columns
to INT
option (option value 16384).
The GetChunk()
and
AppendChunk()
methods from ADO doesn't work
as expected when the cursor location is specified as
adUseServer. On the other hand, you can overcome this error by
using adUseClient.
A simple example can be found from, http://www.dwam.net/iishelp/ado/docs/adomth02_4.htm
You can make use of RecordsAffected
property
in the ADO execute method. For more information on the usage of
execute method, refer to
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/ado270/htm/mdmthcnnexecute.asp.
Here is an excellent article from Mike Hillyer
(<[email protected]>
); explaining how to
insert or fetch data from blob columns through MyODBC from ADO:
MySQL
BLOB columns and Visual Basic 6.
Here is yet another good article from Mike Hillyer
(<[email protected]>
):
How
to map Visual basic data type to MySQL types.
A simple examples for the usage of ADO, DAO and RDO with VB can be found here:
If you find any other good example or HOW-TO on ADO/DAO/RDO,
please send the details to <[email protected]>
For more information about how to access MySQL via ASP using MyODBC, refer to the following articles:
A Frequently Asked Questions list for ASP can be found at http://support.microsoft.com/default.aspx?scid=/Support/ActiveServer/faq/data/adofaq.asp.
For information, see ActiveX Data Objects(ADO) Frequently Asked Questions.
This section answers questions related to MyODBC with various ODBC-related tools; such as Microsoft Word, Excel and ColdFusion.
To retrieve data from MySQL to Word/Excel documents, you need to use the MyODBC driver and the Add-in Microsoft Query help.
For example, create a database with a table containing two columns of text:
Insert rows using the mysql client command-line tool.
Create a DSN file using the ODBC manager, for example,
my
for the database that was just
created.
Open the Word application.
Create a blank new document.
In the Database
tool bar, press the
Insert Database
button.
Press the Get Data
button.
At the right hand of the Get Data
screen,
press the Ms Query
button.
In Ms Query
, create a new data source
using the my
DSN file.
Select the new query.
Select the columns that you want.
Make a filter if you want.
Make a Sort if you want.
Select Return Data to Microsoft Word
.
Click Finish
.
Click Insert Data
and select the records.
Click OK
and you see the rows in your
Word document.
This is an issue similar to that of Access 97 when your table
consists of TEXT
or
VARCHAR
data types. You can fix this error by
upgrading your MyODBC driver to version 3.51.02 or higher.
AUTO_INCREMENT
Column in ODBCTransactions are not enabled
Errors?Cursor not found
Errors?This section of the document answers questions related to MyODBC general functionality.
A common problem is how to get the value of an automatically
generated ID from an INSERT
statement. With
ODBC, you can do something like this (assuming that
auto
is an AUTO_INCREMENT
field):
INSERT INTO tbl (auto,text) VALUES(NULL,'text'); SELECT LAST_INSERT_ID();
Or, if you are just going to insert the ID into another table, you can do this:
INSERT INTO tbl (auto,text) VALUES(NULL,'text'); INSERT INTO tbl2 (id,text) VALUES(LAST_INSERT_ID(),'text');
See Section 25.2.13.3, “How to Get the Unique ID for the Last Inserted Row”.
For the benefit of some ODBC applications (at least Delphi and Access), the following query can be used to find a newly inserted row:
SELECT * FROM tbl WHERE auto IS NULL;
Yes. MyODBC 3.51 supports Dynamic cursor
type
along with Forward-only
and
static
.
Due to the performance issues, the driver does not support this
feature by default. You can enable this by specifying the
connection option flag as OPTION=32
or by
checking the Enable Dynamic Cursor
option
from the DSN configuration.
The driver returns this error when an application issues any transactional call but the underlying MySQL server either does not support transactions or they are not enabled.
To avoid this problem, you must use a server that has either or
both of the InnoDB
or BDB
storage engines enabled, and use tables of those types. MySQL
servers from version 4.0 and up support
InnoDB
by default. MySQL-Max servers also
support BDB
on platforms where
BDB
is available.
Also, if your server supports transactional storage engines
(InnoDB
and BDB
) make sure
the disable transactions
option is not set
from the DSN configuration.
This occurs because the application is using old MyODBC 2.50 version, and it did not set the cursor name explicitly through SQLSetCursorName. The fix is to upgrade to MyODBC 3.51 version.
Yes. If you find something is not working with MyODBC 3.51 that
works with MyODBC 2.50, then send a mail message to
<[email protected]>
Yes. You can make use of odbc.net to connect to MySQL through MyODBC. Here are the few basic samples to connect to MySQL from VC.NET and VB.NET.
Here is yet another excellent article "Exploring MySQL on .NET environment" by Venu (MyODBC developer) that covers about all MySQL .NET interfaces along with some useful examples.
Caution: Using ODBC.NET with MyODBC, while fetching empty string (0 length), it starts giving the SQL_NO_DATA exception. You can get the patch for this from http://support.microsoft.com/default.aspx?scid=kb;EN-US;q319243.
MyODBC is a lot faster than any other ODBC driver. Slowness might be due to not using the following options.
The ODBC Tracing option is turned on. You can cross-check whether this option is not turned on by following the instructions from here.
As shown in the above image, the 'When to trace' option from the ODBC Data Source Administrator 'Tracing' tab should always point to 'Start Tracing Now', instead of 'Stop Tracing Now'.
The Debug version of the driver is used. If you are using the debug version of the driver DLL, it can also relatively slow down the query processing time. You can cross-check whether you are using the debug or release version of the DLL from the 'Comments' section of the driver DLL properties (from the system directory, right click on the driver DLL and click on properties) as shown below:
The Driver trace and query logs are enabled. Even if you intent to use the debug version of the driver (you should always use the release version in the production environment), make sure the driver trace and query log options(OPTION=4,524288 respectively) are not enabled as shown below:
Interacting with a MySQL server from MyODBC applications involves the following operations:
Configure the MyODBC DSN
Connect to MySQL server
Initialization operations
Execute SQL statements
Retrieve results
Perform Transactions
Disconnect from the server
Most applications use some variation of these steps. The basic application steps are shown in the following diagram:
This section summarizes ODBC routines, categorized by functionality.
For the complete ODBC API reference, please refer to the ODBC Programer's Reference at http://msdn.microsoft.com/library/en-us/odbc/htm/odbcabout_this_manual.asp.
An application can call SQLGetInfo
function to
obtain conformance information about MyODBC. To obtain information
about support for a specific function in the driver, an
application can call SQLGetFunctions
.
Note: For backward compatibility, the MyODBC 3.51 driver supports all deprecated functions.
The following tables list MyODBC API calls grouped by task:
Connecting to a data source:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLAllocHandle | No | Yes | ISO 92 | Obtains an environment, connection, statement, or descriptor handle. |
SQLConnect | Yes | Yes | ISO 92 | Connects to a specific driver by data source name, user ID, and password. |
SQLDriverConnect | Yes | Yes | ODBC | Connects to a specific driver by connection string or requests that the Driver Manager and driver display connection dialog boxes for the user. |
SQLAllocEnv | Yes | Yes | Deprecated | Obtains an environment handle allocated from driver. |
SQLAllocConnect | Yes | Yes | Deprecated | Obtains a connection handle |
Obtaining information about a driver and data source:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLDataSources | No | No | ISO 92 | Returns the list of available data sources, handled by the Driver Manager |
SQLDrivers | No | No | ODBC | Returns the list of installed drivers and their attributes, handles by Driver Manager |
SQLGetInfo | Yes | Yes | ISO 92 | Returns information about a specific driver and data source. |
SQLGetFunctions | Yes | Yes | ISO 92 | Returns supported driver functions. |
SQLGetTypeInfo | Yes | Yes | ISO 92 | Returns information about supported data types. |
Setting and retrieving driver attributes:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLSetConnectAttr | No | Yes | ISO 92 | Sets a connection attribute. |
SQLGetConnectAttr | No | Yes | ISO 92 | Returns the value of a connection attribute. |
SQLSetConnectOption | Yes | Yes | Deprecated | Sets a connection option |
SQLGetConnectOption | Yes | Yes | Deprecated | Returns the value of a connection option |
SQLSetEnvAttr | No | Yes | ISO 92 | Sets an environment attribute. |
SQLGetEnvAttr | No | Yes | ISO 92 | Returns the value of an environment attribute. |
SQLSetStmtAttr | No | Yes | ISO 92 | Sets a statement attribute. |
SQLGetStmtAttr | No | Yes | ISO 92 | Returns the value of a statement attribute. |
SQLSetStmtOption | Yes | Yes | Deprecated | Sets a statement option |
SQLGetStmtOption | Yes | Yes | Deprecated | Returns the value of a statement option |
Preparing SQL requests:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLAllocStmt | Yes | Yes | Deprecated | Allocates a statement handle |
SQLPrepare | Yes | Yes | ISO 92 | Prepares an SQL statement for later execution. |
SQLBindParameter | Yes | Yes | ODBC | Assigns storage for a parameter in an SQL statement. |
SQLGetCursorName | Yes | Yes | ISO 92 | Returns the cursor name associated with a statement handle. |
SQLSetCursorName | Yes | Yes | ISO 92 | Specifies a cursor name. |
SQLSetScrollOptions | Yes | Yes | ODBC | Sets options that control cursor behavior. |
Submitting requests:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLExecute | Yes | Yes | ISO 92 | Executes a prepared statement. |
SQLExecDirect | Yes | Yes | ISO 92 | Executes a statement |
SQLNativeSql | Yes | Yes | ODBC | Returns the text of an SQL statement as translated by the driver. |
SQLDescribeParam | Yes | Yes | ODBC | Returns the description for a specific parameter in a statement. |
SQLNumParams | Yes | Yes | ISO 92 | Returns the number of parameters in a statement. |
SQLParamData | Yes | Yes | ISO 92 | Used in conjunction with SQLPutData to supply
parameter data at execution time. (Useful for long data
values.) |
SQLPutData | Yes | Yes | ISO 92 | Sends part or all of a data value for a parameter. (Useful for long data values.) |
Retrieving results and information about results:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLRowCount | Yes | Yes | ISO 92 | Returns the number of rows affected by an insert, update, or delete request. |
SQLNumResultCols | Yes | Yes | ISO 92 | Returns the number of columns in the result set. |
SQLDescribeCol | Yes | Yes | ISO 92 | Describes a column in the result set. |
SQLColAttribute | No | Yes | ISO 92 | Describes attributes of a column in the result set. |
SQLColAttributes | Yes | Yes | Deprecated | Describes attributes of a column in the result set. |
SQLFetch | Yes | Yes | ISO 92 | Returns multiple result rows. |
SQLFetchScroll | No | Yes | ISO 92 | Returns scrollable result rows. |
SQLExtendedFetch | Yes | Yes | Deprecated | Returns scrollable result rows. |
SQLSetPos | Yes | Yes | ODBC | Positions a cursor within a fetched block of data and allows an application to refresh data in the rowset or to update or delete data in the result set. |
SQLBulkOperations | No | Yes | ODBC | Performs bulk insertions and bulk bookmark operations, including update, delete, and fetch by bookmark. |
Retrieving error or diagnostic information:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLError | Yes | Yes | Deprecated | Returns additional error or status information |
SQLGetDiagField | Yes | Yes | ISO 92 | Returns additional diagnostic information (a single field of the diagnostic data structure). |
SQLGetDiagRec | Yes | Yes | ISO 92 | Returns additional diagnostic information (multiple fields of the diagnostic data structure). |
Obtaining information about the data source's system tables (catalog functions) item:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLColumnPrivileges | Yes | Yes | ODBC | Returns a list of columns and associated privileges for one or more tables. |
SQLColumns | Yes | Yes | X/Open | Returns the list of column names in specified tables. |
SQLForeignKeys | Yes | Yes | ODBC | Returns a list of column names that make up foreign keys, if they exist for a specified table. |
SQLPrimaryKeys | Yes | Yes | ODBC | Returns the list of column names that make up the primary key for a table. |
SQLSpecialColumns | Yes | Yes | X/Open | Returns information about the optimal set of columns that uniquely identifies a row in a specified table, or the columns that are automatically updated when any value in the row is updated by a transaction. |
SQLStatistics | Yes | Yes | ISO 92 | Returns statistics about a single table and the list of indexes associated with the table. |
SQLTablePrivileges | Yes | Yes | ODBC | Returns a list of tables and the privileges associated with each table. |
SQLTables | Yes | Yes | X/Open | Returns the list of table names stored in a specific data source. |
Performing transactions:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLTransact | Yes | Yes | Deprecated | Commits or rolls back a transaction |
SQLEndTran | No | Yes | ISO 92 | Commits or rolls back a transaction. |
Terminating a statement:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLFreeStmt | Yes | Yes | ISO 92 | Ends statement processing, discards pending results, and, optionally, frees all resources associated with the statement handle. |
SQLCloseCursor | Yes | Yes | ISO 92 | Closes a cursor that has been opened on a statement handle. |
SQLCancel | Yes | Yes | ISO 92 | Cancels an SQL statement. |
Terminating a connection:
Function name | MyODBC | MyODBC | Conformance | Purpose |
2.50 | 3.51 | |||
SQLDisconnect | Yes | Yes | ISO 92 | Closes the connection. |
SQLFreeHandle | No | Yes | ISO 92 | Releases an environment, connection, statement, or descriptor handle. |
SQLFreeConnect | Yes | Yes | Deprecated | Releases connection handle |
SQLFreeEnv | Yes | Yes | Deprecated | Releases an environment handle |
The following table illustrates how driver maps the server data types to default SQL and C data types:
Native Value | SQL Type | C Type |
bit | SQL_BIT | SQL_C_BIT |
tinyint | SQL_TINYINT | SQL_C_STINYINT |
tinyint unsigned | SQL_TINYINT | SQL_C_UTINYINT |
bigint | SQL_BIGINT | SQL_C_SBIGINT |
bigint unsigned | SQL_BIGINT | SQL_C_UBIGINT |
long varbinary | SQL_LONGVARBINARY | SQL_C_BINARY |
blob | SQL_LONGVARBINARY | SQL_C_BINARY |
longblob | SQL_LONGVARBINARY | SQL_C_BINARY |
tinyblob | SQL_LONGVARBINARY | SQL_C_BINARY |
mediumblob | SQL_LONGVARBINARY | SQL_C_BINARY |
long varchar | SQL_LONGVARCHAR | SQL_C_CHAR |
text | SQL_LONGVARCHAR | SQL_C_CHAR |
mediumtext | SQL_LONGVARCHAR | SQL_C_CHAR |
char | SQL_CHAR | SQL_C_CHAR |
numeric | SQL_NUMERIC | SQL_C_CHAR |
decimal | SQL_DECIMAL | SQL_C_CHAR |
integer | SQL_INTEGER | SQL_C_SLONG |
integer unsigned | SQL_INTEGER | SQL_C_ULONG |
int | SQL_INTEGER | SQL_C_SLONG |
int unsigned | SQL_INTEGER | SQL_C_ULONG |
mediumint | SQL_INTEGER | SQL_C_SLONG |
mediumint unsigned | SQL_INTEGER | SQL_C_ULONG |
smallint | SQL_SMALLINT | SQL_C_SSHORT |
smallint unsigned | SQL_SMALLINT | SQL_C_USHORT |
real | SQL_FLOAT | SQL_C_DOUBLE |
double | SQL_FLOAT | SQL_C_DOUBLE |
float | SQL_REAL | SQL_C_FLOAT |
double precision | SQL_DOUBLE | SQL_C_DOUBLE |
date | SQL_DATE | SQL_C_DATE |
time | SQL_TIME | SQL_C_TIME |
year | SQL_SMALLINT | SQL_C_SHORT |
datetime | SQL_TIMESTAMP | SQL_C_TIMESTAMP |
timestamp | SQL_TIMESTAMP | SQL_C_TIMESTAMP |
text | SQL_VARCHAR | SQL_C_CHAR |
varchar | SQL_VARCHAR | SQL_C_CHAR |
enum | SQL_VARCHAR | SQL_C_CHAR |
set | SQL_VARCHAR | SQL_C_CHAR |
bit | SQL_CHAR | SQL_C_CHAR |
bool | SQL_CHAR | SQL_C_CHAR |
The following tables lists the error codes returned by the driver apart from the server errors.
Native Code | SQLSTATE 2 | SQLSTATE 3 | Error Message |
500 | 01000 | 01000 | General warning |
501 | 01004 | 01004 | String data, right truncated |
502 | 01S02 | 01S02 | Option value changed |
503 | 01S03 | 01S03 | No rows updated/deleted |
504 | 01S04 | 01S04 | More than one row updated/deleted |
505 | 01S06 | 01S06 | Attempt to fetch before the result set returned the first row set |
506 | 07001 | 07002 | SQLBindParameter not used for all parameters |
507 | 07005 | 07005 | Prepared statement not a cursor-specification |
508 | 07009 | 07009 | Invalid descriptor index |
509 | 08002 | 08002 | Connection name in use |
510 | 08003 | 08003 | Connection does not exist |
511 | 24000 | 24000 | Invalid cursor state |
512 | 25000 | 25000 | Invalid transaction state |
513 | 25S01 | 25S01 | Transaction state unknown |
514 | 34000 | 34000 | Invalid cursor name |
515 | S1000 | HY000 | General driver defined error |
516 | S1001 | HY001 | Memory allocation error |
517 | S1002 | HY002 | Invalid column number |
518 | S1003 | HY003 | Invalid application buffer type |
519 | S1004 | HY004 | Invalid SQL data type |
520 | S1009 | HY009 | Invalid use of null pointer |
521 | S1010 | HY010 | Function sequence error |
522 | S1011 | HY011 | Attribute can not be set now |
523 | S1012 | HY012 | Invalid transaction operation code |
524 | S1013 | HY013 | Memory management error |
525 | S1015 | HY015 | No cursor name available |
526 | S1024 | HY024 | Invalid attribute value |
527 | S1090 | HY090 | Invalid string or buffer length |
528 | S1091 | HY091 | Invalid descriptor field identifier |
529 | S1092 | HY092 | Invalid attribute/option identifier |
530 | S1093 | HY093 | Invalid parameter number |
531 | S1095 | HY095 | Function type out of range |
532 | S1106 | HY106 | Fetch type out of range |
533 | S1117 | HY117 | Row value out of range |
534 | S1109 | HY109 | Invalid cursor position |
535 | S1C00 | HYC00 | Optional feature not implemented |
0 | 21S01 | 21S01 | Column count does not match value count |
0 | 23000 | 23000 | Integrity constraint violation |
0 | 42000 | 42000 | Syntax error or access violation |
0 | 42S02 | 42S02 | Base table or view not found |
0 | 42S12 | 42S12 | Index not found |
0 | 42S21 | 42S21 | Column already exists |
0 | 42S22 | 42S22 | Column not found |
0 | 08S01 | 08S01 | Communication link failure |
This section contains simple examples of the use of MySQL ODBC 3.51 Driver with ADO, DAO and RDO.
The following ADO (ActiveX Data Objects) example creates a table
my_ado
and demonstrates the use of
rs.addNew
, rs.delete
, and
rs.update
.
Private Sub myodbc_ado_Click() Dim conn As ADODB.Connection Dim rs As ADODB.Recordset Dim fld As ADODB.Field Dim sql As String 'connect to MySQL server using MySQL ODBC 3.51 Driver Set conn = New ADODB.Connection conn.ConnectionString = "DRIVER={MySQL ODBC 3.51 Driver};"_ & "SERVER=localhost;"_ & " DATABASE=test;"_ & "UID=venu;PWD=venu; OPTION=3" conn.Open 'create table conn.Execute "DROP TABLE IF EXISTS my_ado" conn.Execute "CREATE TABLE my_ado(id int not null primary key, name varchar(20)," _ & "txt text, dt date, tm time, ts timestamp)" 'direct insert conn.Execute "INSERT INTO my_ado(id,name,txt) values(1,100,'venu')" conn.Execute "INSERT INTO my_ado(id,name,txt) values(2,200,'MySQL')" conn.Execute "INSERT INTO my_ado(id,name,txt) values(3,300,'Delete')" Set rs = New ADODB.Recordset rs.CursorLocation = adUseServer 'fetch the initial table .. rs.Open "SELECT * FROM my_ado", conn Debug.Print rs.RecordCount rs.MoveFirst Debug.Print String(50, "-") & "Initial my_ado Result Set " & String(50, "-") For Each fld In rs.Fields Debug.Print fld.Name, Next Debug.Print Do Until rs.EOF For Each fld In rs.Fields Debug.Print fld.Value, Next rs.MoveNext Debug.Print Loop rs.Close 'rs insert rs.Open "select * from my_ado", conn, adOpenDynamic, adLockOptimistic rs.AddNew rs!Name = "Monty" rs!txt = "Insert row" rs.Update rs.Close 'rs update rs.Open "SELECT * FROM my_ado" rs!Name = "update" rs!txt = "updated-row" rs.Update rs.Close 'rs update second time.. rs.Open "SELECT * FROM my_ado" rs!Name = "update" rs!txt = "updated-second-time" rs.Update rs.Close 'rs delete rs.Open "SELECT * FROM my_ado" rs.MoveNext rs.MoveNext rs.Delete rs.Close 'fetch the updated table .. rs.Open "SELECT * FROM my_ado", conn Debug.Print rs.RecordCount rs.MoveFirst Debug.Print String(50, "-") & "Updated my_ado Result Set " & String(50, "-") For Each fld In rs.Fields Debug.Print fld.Name, Next Debug.Print Do Until rs.EOF For Each fld In rs.Fields Debug.Print fld.Value, Next rs.MoveNext Debug.Print Loop rs.Close conn.Close End Sub
The following DAO (Data Access Objects) example creates a table
my_dao
and demonstrates the use of
rs.addNew
, rs.update
, and
result set scrolling.
Private Sub myodbc_dao_Click() Dim ws As Workspace Dim conn As Connection Dim queryDef As queryDef Dim str As String 'connect to MySQL using MySQL ODBC 3.51 Driver Set ws = DBEngine.CreateWorkspace("", "venu", "venu", dbUseODBC) str = "odbc;DRIVER={MySQL ODBC 3.51 Driver};"_ & "SERVER=localhost;"_ & " DATABASE=test;"_ & "UID=venu;PWD=venu; OPTION=3" Set conn = ws.OpenConnection("test", dbDriverNoPrompt, False, str) 'Create table my_dao Set queryDef = conn.CreateQueryDef("", "drop table if exists my_dao") queryDef.Execute Set queryDef = conn.CreateQueryDef("", "create table my_dao(Id INT AUTO_INCREMENT PRIMARY KEY, " _ & "Ts TIMESTAMP(14) NOT NULL, Name varchar(20), Id2 INT)") queryDef.Execute 'Insert new records using rs.addNew Set rs = conn.OpenRecordset("my_dao") Dim i As Integer For i = 10 To 15 rs.AddNew rs!Name = "insert record" & i rs!Id2 = i rs.Update Next i rs.Close 'rs update.. Set rs = conn.OpenRecordset("my_dao") rs.Edit rs!Name = "updated-string" rs.Update rs.Close 'fetch the table back... Set rs = conn.OpenRecordset("my_dao", dbOpenDynamic) str = "Results:" rs.MoveFirst While Not rs.EOF str = " " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2 Debug.Print "DATA:" & str rs.MoveNext Wend 'rs Scrolling rs.MoveFirst str = " FIRST ROW: " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2 Debug.Print str rs.MoveLast str = " LAST ROW: " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2 Debug.Print str rs.MovePrevious str = " LAST-1 ROW: " & rs!Id & " , " & rs!Name & ", " & rs!Ts & ", " & rs!Id2 Debug.Print str 'free all resources rs.Close queryDef.Close conn.Close ws.Close End Sub
The following RDO (Remote Data Objects) example creates a table
my_rdo
and demonstrates the use of
rs.addNew
and rs.update
.
Dim rs As rdoResultset Dim cn As New rdoConnection Dim cl As rdoColumn Dim SQL As String 'cn.Connect = "DSN=test;" cn.Connect = "DRIVER={MySQL ODBC 3.51 Driver};"_ & "SERVER=localhost;"_ & " DATABASE=test;"_ & "UID=venu;PWD=venu; OPTION=3" cn.CursorDriver = rdUseOdbc cn.EstablishConnection rdDriverPrompt 'drop table my_rdo SQL = "drop table if exists my_rdo" cn.Execute SQL, rdExecDirect 'create table my_rdo SQL = "create table my_rdo(id int, name varchar(20))" cn.Execute SQL, rdExecDirect 'insert - direct SQL = "insert into my_rdo values (100,'venu')" cn.Execute SQL, rdExecDirect SQL = "insert into my_rdo values (200,'MySQL')" cn.Execute SQL, rdExecDirect 'rs insert SQL = "select * from my_rdo" Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect) rs.AddNew rs!id = 300 rs!Name = "Insert1" rs.Update rs.Close 'rs insert SQL = "select * from my_rdo" Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect) rs.AddNew rs!id = 400 rs!Name = "Insert 2" rs.Update rs.Close 'rs update SQL = "select * from my_rdo" Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect) rs.Edit rs!id = 999 rs!Name = "updated" rs.Update rs.Close 'fetch back... SQL = "select * from my_rdo" Set rs = cn.OpenResultset(SQL, rdOpenStatic, rdConcurRowVer, rdExecDirect) Do Until rs.EOF For Each cl In rs.rdoColumns Debug.Print cl.Value, Next rs.MoveNext Debug.Print Loop Debug.Print "Row count="; rs.RowCount 'close rs.Close cn.Close End Sub
This section contains simple examples that demonstrate the use of MyODBC drivers with ODBC.NET.
The following sample creates a table
my_odbc_net
and demonstrates the use in C#.
/**
* @sample : mycon.cs
* @purpose : Demo sample for ODBC.NET using MyODBC
* @author : Venu, <[email protected]>
*
* (C) Copyright MySQL AB, 1995-2004
*
**/
/* build command
*
* csc /t:exe
* /out:mycon.exe mycon.cs
* /r:Microsoft.Data.Odbc.dll
*/
using Console = System.Console;
using Microsoft.Data.Odbc;
namespace myodbc3
{
class mycon
{
static void Main(string[] args)
{
try
{
//Connection string for MyODBC 2.50
/*string MyConString = "DRIVER={MySQL};" +
"SERVER=localhost;" +
"DATABASE=test;" +
"UID=venu;" +
"PASSWORD=venu;" +
"OPTION=3";
*/
//Connection string for MyODBC 3.51
string MyConString = "DRIVER={MySQL ODBC 3.51 Driver};" +
"SERVER=localhost;" +
"DATABASE=test;" +
"UID=venu;" +
"PASSWORD=venu;" +
"OPTION=3";
//Connect to MySQL using MyODBC
OdbcConnection MyConnection = new OdbcConnection(MyConString);
MyConnection.Open();
Console.WriteLine("\n !!! success, connected successfully !!!\n");
//Display connection information
Console.WriteLine("Connection Information:");
Console.WriteLine("\tConnection String:" + MyConnection.ConnectionString);
Console.WriteLine("\tConnection Timeout:" + MyConnection.ConnectionTimeout);
Console.WriteLine("\tDatabase:" + MyConnection.Database);
Console.WriteLine("\tDataSource:" + MyConnection.DataSource);
Console.WriteLine("\tDriver:" + MyConnection.Driver);
Console.WriteLine("\tServerVersion:" + MyConnection.ServerVersion);
//Create a sample table
OdbcCommand MyCommand = new OdbcCommand("DROP TABLE IF EXISTS my_odbc_net",MyConnection);
MyCommand.ExecuteNonQuery();
MyCommand.CommandText = "CREATE TABLE my_odbc_net(id int, name varchar(20), idb bigint)";
MyCommand.ExecuteNonQuery();
//Insert
MyCommand.CommandText = "INSERT INTO my_odbc_net VALUES(10,'venu', 300)";
Console.WriteLine("INSERT, Total rows affected:" + MyCommand.ExecuteNonQuery());;
//Insert
MyCommand.CommandText = "INSERT INTO my_odbc_net VALUES(20,'mysql',400)";
Console.WriteLine("INSERT, Total rows affected:" + MyCommand.ExecuteNonQuery());
//Insert
MyCommand.CommandText = "INSERT INTO my_odbc_net VALUES(20,'mysql',500)";
Console.WriteLine("INSERT, Total rows affected:" + MyCommand.ExecuteNonQuery());
//Update
MyCommand.CommandText = "UPDATE my_odbc_net SET id=999 WHERE id=20";
Console.WriteLine("Update, Total rows affected:" + MyCommand.ExecuteNonQuery());
//COUNT(*)
MyCommand.CommandText = "SELECT COUNT(*) as TRows FROM my_odbc_net";
Console.WriteLine("Total Rows:" + MyCommand.ExecuteScalar());
//Fetch
MyCommand.CommandText = "SELECT * FROM my_odbc_net";
OdbcDataReader MyDataReader;
MyDataReader = MyCommand.ExecuteReader();
while (MyDataReader.Read())
{
if(string.Compare(MyConnection.Driver,"myodbc3.dll") == 0) {
Console.WriteLine("Data:" + MyDataReader.GetInt32(0) + " " +
MyDataReader.GetString(1) + " " +
MyDataReader.GetInt64(2)); //Supported only by MyODBC 3.51
}
else {
Console.WriteLine("Data:" + MyDataReader.GetInt32(0) + " " +
MyDataReader.GetString(1) + " " +
MyDataReader.GetInt32(2)); //BIGINTs not supported by MyODBC
}
}
//Close all resources
MyDataReader.Close();
MyConnection.Close();
}
catch (OdbcException MyOdbcException)//Catch any ODBC exception ..
{
for (int i=0; i < MyOdbcException.Errors.Count; i++)
{
Console.Write("ERROR #" + i + "\n" +
"Message: " + MyOdbcException.Errors[i].Message + "\n" +
"Native: " + MyOdbcException.Errors[i].NativeError.ToString() + "\n" +
"Source: " + MyOdbcException.Errors[i].Source + "\n" +
"SQL: " + MyOdbcException.Errors[i].SQLState + "\n");
}
}
}
}
}
The following sample creates a table
my_vb_net
and demonstrates the use in VB.
' @sample : myvb.vb
' @purpose : Demo sample for ODBC.NET using MyODBC
' @author : Venu, <[email protected]>
'
' (C) Copyright MySQL AB, 1995-2004
'
'
'
' build command
'
' vbc /target:exe
' /out:myvb.exe
' /r:Microsoft.Data.Odbc.dll
' /r:System.dll
' /r:System.Data.dll
'
Imports Microsoft.Data.Odbc
Imports System
Module myvb
Sub Main()
Try
'MyODBC 3.51 connection string
Dim MyConString As String = "DRIVER={MySQL ODBC 3.51 Driver};" & _
"SERVER=localhost;" & _
"DATABASE=test;" & _
"UID=venu;" & _
"PASSWORD=venu;" & _
"OPTION=3;"
'Connection
Dim MyConnection As New OdbcConnection(MyConString)
MyConnection.Open()
Console.WriteLine ("Connection State::" & MyConnection.State.ToString)
'Drop
Console.WriteLine ("Dropping table")
Dim MyCommand As New OdbcCommand()
MyCommand.Connection = MyConnection
MyCommand.CommandText = "DROP TABLE IF EXISTS my_vb_net"
MyCommand.ExecuteNonQuery()
'Create
Console.WriteLine ("Creating....")
MyCommand.CommandText = "CREATE TABLE my_vb_net(id int, name varchar(30))"
MyCommand.ExecuteNonQuery()
'Insert
MyCommand.CommandText = "INSERT INTO my_vb_net VALUES(10,'venu')"
Console.WriteLine("INSERT, Total rows affected:" & MyCommand.ExecuteNonQuery())
'Insert
MyCommand.CommandText = "INSERT INTO my_vb_net VALUES(20,'mysql')"
Console.WriteLine("INSERT, Total rows affected:" & MyCommand.ExecuteNonQuery())
'Insert
MyCommand.CommandText = "INSERT INTO my_vb_net VALUES(20,'mysql')"
Console.WriteLine("INSERT, Total rows affected:" & MyCommand.ExecuteNonQuery())
'Insert
MyCommand.CommandText = "INSERT INTO my_vb_net(id) VALUES(30)"
Console.WriteLine("INSERT, Total rows affected:" & MyCommand.ExecuteNonQuery())
'Update
MyCommand.CommandText = "UPDATE my_vb_net SET id=999 WHERE id=20"
Console.WriteLine("Update, Total rows affected:" & MyCommand.ExecuteNonQuery())
'COUNT(*)
MyCommand.CommandText = "SELECT COUNT(*) as TRows FROM my_vb_net"
Console.WriteLine("Total Rows:" & MyCommand.ExecuteScalar())
'Select
Console.WriteLine ("Select * FROM my_vb_net")
MyCommand.CommandText = "SELECT * FROM my_vb_net"
Dim MyDataReader As OdbcDataReader
MyDataReader = MyCommand.ExecuteReader
While MyDataReader.Read
If MyDataReader("name") Is DBNull.Value Then
Console.WriteLine ("id = " & CStr(MyDataReader("id")) & " name = " & _
"NULL")
Else
Console.WriteLine ("id = " & CStr(MyDataReader("id")) & " name = " & _
CStr(MyDataReader("name")))
End If
End While
'Catch ODBC Exception
Catch MyOdbcException As OdbcException
Dim i As Integer
Console.WriteLine (MyOdbcException.ToString)
'Catch program exception
Catch MyException As Exception
Console.WriteLine (MyException.ToString)
End Try
End Sub
End Module
MySQL Connector/NET enables developers to easily create .NET applications that require secure, high-performance data connectivity with MySQL. It implements the required ADO.NET interfaces and integrates into ADO.NET aware tools. Developers can build applications using their choice of .NET languages. MySQL Connector/NET is a fully managed ADO.NET driver written in 100% pure C#.
MySQL Connector/NET includes full support for:
MySQL 5.0 features (such as stored procedures)
MySQL 4.1 features (server-side prepared statements, Unicode, and shared memory access, and so forth)
Large-packet support for sending and receiving rows and BLOBs up to 2 gigabytes in size.
Protocol compression which allows for compressing the data stream between the client and server.
Support for connecting using TCP/IP sockets, named pipes, or shared memory on Windows.
Support for connecting using TCP/IP sockets or Unix sockets on Unix.
Support for the Open Source Mono framework developed by Novell.
Fully managed, does not utilize the MySQL client library.
The developers of MySQL Connector/NET greatly value the input of our users in the software development process. If you find MySQL Connector/NET lacking some feature important to you, or if you discover a bug and need to file a bug report, please use the instructions in Section 1.8, “How to Report Bugs or Problems”.
Additional resources
Community support for MySQL Connector/NET can be found through the forums at http://forums.mysql.com.
Community support for MySQL Connector/NET can also be found through the mailing lists at http://lists.mysql.com.
Paid support is available from MySQL AB. Additional information is available at http://www.mysql.com/support/.
This document is intended as a user's guide to MySQL Connector/NET and
not as a syntax reference. If you need detailed syntax information
you should read the Documentation.chm
file
included with the MySQL Connector/NET distribution.
MySQL Connector/NET runs on any platform that supports the .NET framework. The .NET framework is primarily supported on recent versions of Microsoft Windows, and is supported on Linux through the Open Source Mono framework developed by Novell (see http://www.mono-project.com).
MySQL Connector/NET is installed through the use of a Windows
Installer (.msi
) installation package, which
can be used to install MySQL Connector/NET on all Windows operating
systems. The MSI package in contained within a ZIP archive named
mysql-connector-net-
,
where version
.zipversion
indicates the
MySQL Connector/NET version.
MySQL Connector/NET is available for download from http://dev.mysql.com/downloads/connector/net/1.0.html.
The Windows Installer engine was updated with the release of Windows XP; those using an older version can reference this Microsoft Knowledge Base article for information on upgrading to the latest version.
To install MySQL Connector/NET, right-click on the MSI file and select
Typical
installation is recommended for most users.
If you are having problems running the installer, you can download
a ZIP file without an installer as an alternative. That file is
called
mysql-connector-net-
.
Using a ZIP program, unpack it to a directory of your choice.
version
-noinstall.zip
Unless you choose otherwise, MySQL Connector/NET is installed in
C:\Program Files\MySQL\MySQL Connector Net
, where
X.X.X
X.X.X
is replaced with the version of
MySQL Connector/NET you are installing. New installations do not
overwrite existing versions of MySQL Connector/NET.
MySQL Connector/NET comprises several classes that are used to connect to the database, execute queries and statements, and manage query results.
The following are the major classes of MySQL Connector/NET:
MySqlCommand
: Represents an SQL statement
to execute against a MySQL database.
MySqlCommandBuilder
: Automatically
generates single-table commands used to reconcile changes made
to a DataSet with the associated MySQL database.
MySqlConnection
: Represents an open
connection to a MySQL Server database.
MySqlDataAdapter
: Represents a set of data
commands and a database connection that are used to fill a
dataset and update a MySQL database.
MySqlDataReader
: Provides a means of
reading a forward-only stream of rows from a MySQL database.
MySqlException
: The exception that is
thrown when MySQL returns an error.
MySqlHelper
: Helper class that makes it
easier to work with the provider.
MySqlTransaction
: Represents an SQL
transaction to be made in a MySQL database.
Each of these objects will be described in the upcoming sections.
These sections are intended to be an overview of the major classes
of MySQL Connector/NET, and not a syntax reference. If you need more
detailed information you should read the
Documentation.chm
file included with the
MySQL Connector/NET distribution.
The MySqlCommand
class represents an SQL
statement to execute against a MySQL database.
Note: Prior versions of the provider used the '@' symbol to mark parameters in SQL. This is incompatible with MySQL user variables, so the provider now uses the '?' symbol to locate parameters in SQL. To support older code, you can set 'old syntax=yes' in your connection string. If you do this, please be aware that an exception will not be thrown if you fail to define a parameter that you intended to use in your SQL.
The following properties are available:
CommandText
: Gets or sets the SQL
statement to execute at the data source.
CommandTimeout
: Gets or sets the wait
time before terminating the attempt to execute a command
and generating an error.
CommandType
: Gets or sets a value
indicating how the CommandText property is to be
interpreted. Possible types are
StoredProcedure
,
TableDirect
, and
Text
.
Connection
: Gets or sets the
MySqlConnection used by this instance of the MySqlCommand.
IsPrepared
: Is true if this command has
been prepared, false otherwise.
Parameters
: Gets the
MySqlParameterCollection.
Transaction
: Gets or sets the
MySqlTransaction within which the MySqlCommand executes.
UpdatedRowSource
: Gets or sets how
command results are applied to the DataRow when used by
the Update method of the DbDataAdapter.
The following methods are available:
Cancel
: Attempts to cancel the
execution of a MySqlCommand. This operation is
not supported.
Clone
: Creates a clone of this
MySqlCommand object. CommandText, Connection, and
Transaction properties are included as well as the entire
parameter list.
CreateParameter
: Creates a new instance
of a MySqlParameter object.
Dispose
: Disposes of this instance of
MySqlCommand.
ExecuteNonQuery
: Executes an SQL
statement against the connection and returns the number of
rows affected.
ExecuteReader
: Sends the CommandText to
the Connection and builds a MySqlDataReader.
ExecuteScalar
: Executes the query, and
returns the first column of the first row in the result
set returned by the query. Extra columns or rows are
ignored.
Prepare
: Creates a prepared version of
the command on an instance of MySQL Server.
The following example creates a MySqlCommand and a MySqlConnection. The MySqlConnection is opened and set as the Connection for the MySqlCommand. The example then calls ExecuteNonQuery, and closes the connection. To accomplish this, the ExecuteNonQuery is passed a connection string and a query string that is an SQL INSERT statement.
The following example show how to use the MySqlCommand class with VB.NET:
Public Sub InsertRow(myConnectionString As String) ' If the connection string is null, use a default. If myConnectionString = "" Then myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass" End If Dim myConnection As New MySqlConnection(myConnectionString) Dim myInsertQuery As String = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)" Dim myCommand As New MySqlCommand(myInsertQuery) myCommand.Connection = myConnection myConnection.Open() myCommand.ExecuteNonQuery() myCommand.Connection.Close() End Sub
The following example show how to use the MySqlCommand class with C#:
public void InsertRow(string myConnectionString) { // If the connection string is null, use a default. if(myConnectionString == "") { myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass"; } MySqlConnection myConnection = new MySqlConnection(myConnectionString); string myInsertQuery = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)"; MySqlCommand myCommand = new MySqlCommand(myInsertQuery); myCommand.Connection = myConnection; myConnection.Open(); myCommand.ExecuteNonQuery(); myCommand.Connection.Close(); }
The MySqlDataAdapter does not automatically generate the SQL statements required to reconcile changes made to a DataSet with the associated instance of MySQL. However, you can create a MySqlCommandBuilder object to automatically generate SQL statements for single-table updates if you set the SelectCommand property of the MySqlDataAdapter. Then, any additional SQL statements that you do not set are generated by the MySqlCommandBuilder.
The MySqlCommandBuilder registers itself as a listener for OnRowUpdating events whenever you set the DataAdapter property. You can only associate one MySqlDataAdapter or MySqlCommandBuilder object with each other at one time.
To generate INSERT, UPDATE, or DELETE statements, the MySqlCommandBuilder uses the SelectCommand property to retrieve a required set of metadata automatically. If you change the SelectCommand after the metadata has is retrieved (for example, after the first update), you should call the RefreshSchema method to update the metadata.
The SelectCommand must also return at least one primary key or unique column. If none are present, an InvalidOperation exception is generated, and the commands are not generated.
The MySqlCommandBuilder also uses the Connection, CommandTimeout, and Transaction properties referenced by the SelectCommand. The user should call RefreshSchema if any of these properties are modified, or if the SelectCommand itself is replaced. Otherwise the InsertCommand, UpdateCommand, and DeleteCommand properties retain their previous values.
If you call Dispose, the MySqlCommandBuilder is disassociated from the MySqlDataAdapter, and the generated commands are no longer used.
The following properties are available:
DataAdapter
: The MySqlCommandBuilder
registers itself as a listener for RowUpdating events that
are generated by the MySqlDataAdapter specified in this
property. When you create a new instance
MySqlCommandBuilder, any existing MySqlCommandBuilder
associated with this MySqlDataAdapter is released.
QuotePrefix
,
QuoteSuffix
: Database objects in MySQL
can contain special characters such as spaces that would
make normal SQL strings impossible to correctly parse. Use
of the QuotePrefix and the QuoteSuffix properties allows
the MySqlCommandBuilder to build SQL commands that handle
this situation.
The following methods are available:
DeriveParameters
: Retrieves parameter
information from the stored procedure specified in the
MySqlCommand and populates the Parameters collection of
the specified MySqlCommand object. This method is not
currently supported because stored procedures are not
available in MySql.
GetDeleteCommand
: Gets the
automatically generated MySqlCommand object required to
perform deletions on the database.
GetInsertCommand
: Gets the
automatically generated MySqlCommand object required to
perform insertions on the database.
GetUpdateCommand
: Gets the
automatically generated MySqlCommand object required to
perform updates on the database.
RefreshSchema
: Refreshes the database
schema information used to generate INSERT, UPDATE, or
DELETE statements.
The following example uses the MySqlCommand, along MySqlDataAdapter and MySqlConnection, to select rows from a data source. The example is passed an initialized DataSet, a connection string, a query string that is an SQL SELECT statement, and a string that is the name of the database table. The example then creates a MySqlCommandBuilder.
The following example shows how to use the MySqlCommandBuilder class with VB.NET:
Public Shared Function SelectRows(myConnection As String, mySelectQuery As String, myTableName As String) As DataSet Dim myConn As New MySqlConnection(myConnection) Dim myDataAdapter As New MySqlDataAdapter() myDataAdapter.SelectCommand = New MySqlCommand(mySelectQuery, myConn) Dim cb As SqlCommandBuilder = New MySqlCommandBuilder(myDataAdapter) myConn.Open() Dim ds As DataSet = New DataSet myDataAdapter.Fill(ds, myTableName) ' Code to modify data in DataSet here ' Without the MySqlCommandBuilder this line would fail. myDataAdapter.Update(ds, myTableName) myConn.Close() End Function 'SelectRows
The following example shows how to use the MySqlCommandBuilder class with C#:
public static DataSet SelectRows(string myConnection, string mySelectQuery, string myTableName) { MySqlConnection myConn = new MySqlConnection(myConnection); MySqlDataAdapter myDataAdapter = new MySqlDataAdapter(); myDataAdapter.SelectCommand = new MySqlCommand(mySelectQuery, myConn); MySqlCommandBuilder cb = new MySqlCommandBuilder(myDataAdapter); myConn.Open(); DataSet ds = new DataSet(); myDataAdapter.Fill(ds, myTableName); //code to modify data in DataSet here //Without the MySqlCommandBuilder this line would fail myDataAdapter.Update(ds, myTableName); myConn.Close(); return ds; }
A MySqlConnection object represents a session to a MySQL Server data source. When you create an instance of MySqlConnection, all properties are set to their initial values. For a list of these values, see the MySqlConnection constructor.
If the MySqlConnection goes out of scope, it is not closed. Therefore, you must explicitly close the connection by calling Close or Dispose.
The following properties are available:
ConnectionString
: Gets or sets the
string used to connect to a MySQL Server database.
ConnectionTimeout
: Gets the time to
wait while trying to establish a connection before
terminating the attempt and generating an error.
Database
: Gets the name of the current
database or the database to be used after a connection is
opened.
DataSource
: Gets the name of the MySQL
server to which to connect.
ServerThread
: Returns the id of the
server thread this connection is executing on.
ServerVersion
: Gets a string containing
the version of the MySQL server to which the client is
connected.
State
: Gets the current state of the
connection.
UseConnection
: Indicates if this
connection should use compression when communicating with
the server.
The following methods are available:
BeginTransaction
: Begins a database
transaction.
ChangeDatabase
: Changes the current
database for an open MySqlConnection.
Close
: Closes the connection to the
database. This is the preferred method of closing any open
connection.
CreateCommand
: Creates and returns a
MySqlCommand object associated with the MySqlConnection.
Dispose
: Releases the resources used by
the MySqlConnection.
Open
: Opens a database connection with
the property settings specified by the ConnectionString.
Ping
: Pings the MySQL server.
The following example creates a MySqlCommand and a MySqlConnection. The MySqlConnection is opened and set as the Connection for the MySqlCommand. The example then calls ExecuteNonQuery, and closes the connection. To accomplish this, the ExecuteNonQuery is passed a connection string and a query string that is an SQL INSERT statement.
The following example shows how to use the MySqlConnection class with VB.NET:
Public Sub InsertRow(myConnectionString As String) ' If the connection string is null, use a default. If myConnectionString = "" Then myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass" End If Dim myConnection As New MySqlConnection(myConnectionString) Dim myInsertQuery As String = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)" Dim myCommand As New MySqlCommand(myInsertQuery) myCommand.Connection = myConnection myConnection.Open() myCommand.ExecuteNonQuery() myCommand.Connection.Close() End Sub
The following example shows how to use the MySqlConnection class with C#:
public void InsertRow(string myConnectionString) { // If the connection string is null, use a default. if(myConnectionString == "") { myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass"; } MySqlConnection myConnection = new MySqlConnection(myConnectionString); string myInsertQuery = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)"; MySqlCommand myCommand = new MySqlCommand(myInsertQuery); myCommand.Connection = myConnection; myConnection.Open(); myCommand.ExecuteNonQuery(); myCommand.Connection.Close(); }
The MySQLDataAdapter serves as a bridge between a DataSet and MySQL for retrieving and saving data. The MySQLDataAdapter provides this bridge by mapping Fill, which changes the data in the DataSet to match the data in the data source, and Update, which changes the data in the data source to match the data in the DataSet, using the appropriate SQL statements against the data source.
When the MySQLDataAdapter fills a DataSet, it will create the necessary tables and columns for the returned data if they do not already exist. However, primary key information will not be included in the implicitly created schema unless the MissingSchemaAction property is set to AddWithKey. You may also have the MySQLDataAdapter create the schema of the DataSet, including primary key information, before filling it with data using FillSchema.
MySQLDataAdapter is used in conjunction with MySqlConnection and MySqlCommand to increase performance when connecting to a MySQL database.
The MySQLDataAdapter also includes the SelectCommand, InsertCommand, DeleteCommand, UpdateCommand, and TableMappings properties to facilitate the loading and updating of data.
The following properties are available:
AcceptChangesDuringFill
: Gets or sets a
value indicating whether AcceptChanges is called on a
DataRow after it is added to the DataTable during any of
the Fill operations.
ContinueUpdateOnError
: Gets or sets a
value that specifies whether to generate an exception when
an error is encountered during a row update.
DeleteCommand
: Gets or sets an SQL
statement or stored procedure used to delete records from
the data set.
InsertCommand
: Gets or sets an SQL
statement or stored procedure used to insert records into
the data set.
MissingMappingAction
: Determines the
action to take when incoming data does not have a matching
table or column.
MissingSchemaAction
: Determines the
action to take when existing DataSet schema does not match
incoming data.
SelectCommand
: Gets or sets an SQL
statement or stored procedure used to select records in
the data source.
TableMappings
: Gets a collection that
provides the master mapping between a source table and a
DataTable.
UpdateCommand
: Gets or sets an SQL
statement or stored procedure used to updated records in
the data source.
The following methods are available:
Fill
: Adds or refreshes rows in the
DataSet to match those in the data source using the
DataSet name, and creates a DataTable named "Table".
FillSchema
: Adds a DataTable named
"Table" to the specified DataSet and configures the schema
to match that in the data source based on the specified
SchemaType.
GetFillParameters
: Gets the parameters
set by the user when executing an SQL SELECT statement.
Update
: Calls the respective INSERT,
UPDATE, or DELETE statements for each inserted, updated,
or deleted row in the specified DataSet.
The following example creates a MySqlCommand and a MySqlConnection. The MySqlConnection is opened and set as the Connection for the MySqlCommand. The example then calls ExecuteNonQuery, and closes the connection. To accomplish this, the ExecuteNonQuery is passed a connection string and a query string that is an SQL INSERT statement.
The following example shows how to use the MySqlDataAdapter class with VB.NET:
Public Function SelectRows(dataSet As DataSet, connection As String, query As String) As DataSet Dim conn As New MySqlConnection(connection) Dim adapter As New MySqlDataAdapter() adapter.SelectCommand = new MySqlCommand(query, conn) adapter.Fill(dataset) Return dataset End Function
The following example shows how to use the MySqlDataAdapter class with C#:
public DataSet SelectRows(DataSet dataset,string connection,string query) { MySqlConnection conn = new MySqlConnection(connection); MySqlDataAdapter adapter = new MySqlDataAdapter(); adapter.SelectCommand = new MySqlCommand(query, conn); adapter.Fill(dataset); return dataset; }
The MySqlDataReader class provides a means of reading a forward-only stream of rows from a MySQL database.
To create a MySQLDataReader, you must call the ExecuteReader method of the MySqlCommand object, rather than directly using a constructor.
While the MySqlDataReader is in use, the associated MySqlConnection is busy serving the MySqlDataReader, and no other operations can be performed on the MySqlConnection other than closing it. This is the case until the Close method of the MySqlDataReader is called.
IsClosed and RecordsAffected are the only properties that you can call after the MySqlDataReader is closed. Though the RecordsAffected property may be accessed at any time while the MySqlDataReader exists, always call Close before returning the value of RecordsAffected to ensure an accurate return value.
For optimal performance, MySqlDataReader avoids creating unnecessary objects or making unnecessary copies of data. As a result, multiple calls to methods such as GetValue return a reference to the same object. Use caution if you are modifying the underlying value of the objects returned by methods such as GetValue.
The following properties are available:
Depth
: Gets a value indicating the
depth of nesting for the current row. This method is not
supported currently and always returns 0.
FieldCount
: Gets the number of columns
in the current row.
HasRows
: Gets a value indicating
whether the MySqlDataReader contains one or more rows.
IsClosed
: Gets a value indicating
whether the data reader is closed.
Item
: Gets the value of a column in its
native format. In C#, this property is the indexer for the
MySqlDataReader class.
RecordsAffected
: Gets the number of
rows changed, inserted, or deleted by execution of the SQL
statement.
The following methods are available:
Close
: Closes the MySqlDataReader
object.
GetBoolean
: Gets the value of the
specified column as a Boolean.
GetByte
: Gets the value of the
specified column as a byte.
GetBytes
: Reads a stream of bytes from
the specified column offset into the buffer an array
starting at the given buffer offset.
GetChar
: Gets the value of the
specified column as a single character.
GetChars
: Reads a stream of characters
from the specified column offset into the buffer as an
array starting at the given buffer offset.
GetDataTypeName
: Gets the name of the
source data type.
GetDateTime
: Gets the value of the
specified column as a DateTime object.
GetDecimal
: Gets the value of the
specified column as a Decimal object.
GetDouble
: Gets the value of the
specified column as a double-precision floating point
number.
GetFieldType
: Gets the Type that is the
data type of the object.
GetFloat
: Gets the value of the
specified column as a single-precision floating point
number.
GetGuid
: Gets the value of the
specified column as a GUID.
GetInt16
: Gets the value of the
specified column as a 16-bit signed integer.
GetInt32
: Gets the value of the
specified column as a 32-bit signed integer.
GetInt64
: Gets the value of the
specified column as a 64-bit signed integer.
GetMySqlDateTime
: Gets the value of the
specified column as a MySqlDateTime object.
GetName
: Gets the name of the specified
column.
GetOrdinal
: Gets the column ordinal,
given the name of the column.
GetSchemaTable
: Returns a DataTable
that describes the column metadata of the MySqlDataReader.
GetString
: Gets the value of the
specified column as a String object.
GetTimeSpan
: Gets the value of the
specified column as a TimeSpan object.
GetUInt16
: Gets the value of the
specified column as a 16-bit unsigned integer.
GetUInt32
: Gets the value of the
specified column as a 32-bit unsigned integer.
GetUInt64
: Gets the value of the
specified column as a 64-bit unsigned integer.
GetValue
: Gets the value of the
specified column in its native format.
GetValues
: Gets all attribute columns
in the collection for the current row.
IsDBNull
: Gets a value indicating
whether the column contains non-existent or missing
values.
NextResult
: Advances the data reader to
the next result, when reading the results of batch SQL
statements.
Read
: Advances the MySqlDataReader to
the next record.
The following example creates a MySqlConnection, a MySqlCommand, and a MySqlDataReader. The example reads through the data, writing it out to the console. Finally, the example closes the MySqlDataReader, then the MySqlConnection
The following example shows how to use the MySqlDataReader class with VB.NET:
Public Sub ReadMyData(myConnString As String) Dim mySelectQuery As String = "SELECT OrderID, CustomerID FROM Orders" Dim myConnection As New MySqlConnection(myConnString) Dim myCommand As New MySqlCommand(mySelectQuery, myConnection) myConnection.Open() Dim myReader As MySqlDataReader myReader = myCommand.ExecuteReader() ' Always call Read before accessing data. While myReader.Read() Console.WriteLine((myReader.GetInt32(0) & ", " & myReader.GetString(1))) End While ' always call Close when done reading. myReader.Close() ' Close the connection when done with it. myConnection.Close() End Sub 'ReadMyData
The following example shows how to use the MySqlDataReader class with C#:
public void ReadMyData(string myConnString) { string mySelectQuery = "SELECT OrderID, CustomerID FROM Orders"; MySqlConnection myConnection = new MySqlConnection(myConnString); MySqlCommand myCommand = new MySqlCommand(mySelectQuery,myConnection); myConnection.Open(); MySqlDataReader myReader; myReader = myCommand.ExecuteReader(); // Always call Read before accessing data. while (myReader.Read()) { Console.WriteLine(myReader.GetInt32(0) + ", " + myReader.GetString(1)); } // always call Close when done reading. myReader.Close(); // Close the connection when done with it. myConnection.Close(); }
This class is created whenever the MySql Data Provider encounters an error generated from the server.
Any open connections are not automatically closed when an exception is thrown. If the client application determines that the exception is fatal, it should close any open MySqlDataReader objects or MySqlConnection objects.
The following properties are available:
HelpLink
: Gets or sets a link to the
help file associated with this exception.
InnerException
: Gets the Exception
instance that caused the current exception.
IsFatal
: True if this exception was
fatal and cause the closing of the connection, false
otherwise.
Message
: Gets a message that describes
the current exception.
Number
: Gets a number that identifies
the type of error.
Source
: Gets or sets the name of the
application or the object that causes the error.
StackTrace
: Gets a string
representation of the frames on the call stack at the time
the current exception was thrown.
TargetSite
: Gets the method that throws
the current exception.
The following example generates a MySqlException due to a missing server, and then displays the exception.
This example demonstrates how to use the MySqlException class with VB.NET:
Public Sub ShowException() Dim mySelectQuery As String = "SELECT column1 FROM table1" Dim myConnection As New MySqlConnection ("Data Source=localhost;Database=Sample;") Dim myCommand As New MySqlCommand(mySelectQuery, myConnection) Try myCommand.Connection.Open() Catch e As MySqlException MessageBox.Show( e.Message ) End Try End Sub
This example demonstrates how to use the MySqlException class with C#:
public void ShowException() { string mySelectQuery = "SELECT column1 FROM table1"; MySqlConnection myConnection = new MySqlConnection("Data Source=localhost;Database=Sample;"); MySqlCommand myCommand = new MySqlCommand(mySelectQuery,myConnection); try { myCommand.Connection.Open(); } catch (MySqlException e) { MessageBox.Show( e.Message ); } }
Helper class that makes it easier to work with the provider. Developers can use the methods of this class to automatically perform common tasks.
The following methods are available:
ExecuteDataRow
: Executes a single SQL
command and returns the first row of the resultset. A new
MySqlConnection object is created, opened, and closed
during this method.
ExecuteDataset
: Executes a single SQL
command and returns the resultset in a DataSet. A new
MySqlConnection object is created, opened, and closed
during this method.
ExecuteNonQuery
: Executes a single
command against a MySQL database. The MySqlConnection is
assumed to be open when the method is called and remains
open after the method completes.
ExecuteReader
: Overloaded. Executes a
single command against a MySQL database.
ExecuteScalar
: Execute a single command
against a MySQL database.
UpdateDataSet
: Updates the given table
with data from the given DataSet.
Represents an SQL transaction to be made in a MySQL database.
The following properties are available:
Connection
: Gets the MySqlConnection
object associated with the transaction, or a null
reference (Nothing in Visual Basic) if the transaction is
no longer valid.
IsolationLevel
: Specifies the
IsolationLevel for this transaction.
The following methods are available:
Commit
: Commits the database
transaction.
Rollback
: Rolls back a transaction from
a pending state.
The following example creates a MySqlConnection and a MySqlTransaction. It also demonstrates how to use the BeginTransaction, Commit, and Rollback methods.
The following example shows how to use the MySqlTransaction class with VB.NET:
Public Sub RunTransaction(myConnString As String) Dim myConnection As New MySqlConnection(myConnString) myConnection.Open() Dim myCommand As MySqlCommand = myConnection.CreateCommand() Dim myTrans As MySqlTransaction ' Start a local transaction myTrans = myConnection.BeginTransaction() ' Must assign both transaction object and connection ' to Command object for a pending local transaction myCommand.Connection = myConnection myCommand.Transaction = myTrans Try myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')" myCommand.ExecuteNonQuery() myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')" myCommand.ExecuteNonQuery() myTrans.Commit() Console.WriteLine("Both records are written to database.") Catch e As Exception Try myTrans.Rollback() Catch ex As MySqlException If Not myTrans.Connection Is Nothing Then Console.WriteLine("An exception of type " & ex.GetType().ToString() & _ " was encountered while attempting to roll back the transaction.") End If End Try Console.WriteLine("An exception of type " & e.GetType().ToString() & _ "was encountered while inserting the data.") Console.WriteLine("Neither record was written to database.") Finally myConnection.Close() End Try End Sub 'RunTransaction
The following example shows how to use the MySqlTransaction class with C#:
public void RunTransaction(string myConnString) { MySqlConnection myConnection = new MySqlConnection(myConnString); myConnection.Open(); MySqlCommand myCommand = myConnection.CreateCommand(); MySqlTransaction myTrans; // Start a local transaction myTrans = myConnection.BeginTransaction(); // Must assign both transaction object and connection // to Command object for a pending local transaction myCommand.Connection = myConnection; myCommand.Transaction = myTrans; try { myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')"; myCommand.ExecuteNonQuery(); myCommand.CommandText = "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')"; myCommand.ExecuteNonQuery(); myTrans.Commit(); Console.WriteLine("Both records are written to database."); } catch(Exception e) { try { myTrans.Rollback(); } catch (MySqlException ex) { if (myTrans.Connection != null) { Console.WriteLine("An exception of type " + ex.GetType() + " was encountered while attempting to roll back the transaction."); } } Console.WriteLine("An exception of type " + e.GetType() + " was encountered while inserting the data."); Console.WriteLine("Neither record was written to database."); } finally { myConnection.Close(); } }
In this section we will cover some of the more common use cases for Connector/NET, including BLOB handling, date handling, and using Connector/NET with common tools such as Crystal Reports.
All interaction between a .NET application and the MySQL
server is routed through a MySqlConnection
object. Before your application can interact with the server,
a MySqlConnection
object must be instanced,
configured, and opened.
Even when using the MySqlHelper
class, a
MySqlConnection
object is created by the
helper class.
In this section, we will describe how to connect to MySQL
using the MySqlConnection
object.
The MySqlConnection
object is configured
using a connection string. A connection string contains sever
key/value pairs, separated by semicolons. Each key/value pair
is joined with an equals sign.
The following is a sample connection string:
Server=127.0.0.1;Uid=root;Pwd=12345;Database=test;
In this example, the MySqlConnection
object
is configured to connect to a MySQL server at
127.0.0.1
, with a username of
root
and a password of
12345
. The default database for all
statements will be the test
database.
The following options are typically used (a full list of options is available in the API documentation):
Server
: The name or network address of
the instance of MySQL to which to connect. The default is
localhost
. Aliases include
host
, Data Source
,
DataSource
, Address
,
Addr
and Network
Address
.
Uid
: The MySQL user account to use when
connecting. Aliases include User Id
,
Username
and User
name
.
Pwd
: The password for the MySQL account
being used. Alias Password
can also be
used.
Database
: The default database that all
statements are applied to. Default is
mysql
. Alias Initial
Catalog
can also be used.
Port
: The port MySQL is using to listen
for connections. Default is 3306
.
Specify -1
for this value to use a
named pipe connection.
Once you have created a connection string it can be used to open a connection to the MySQL server.
The following code is used to create a
MySqlConnection
object, assign the
connection string, and open the connection.
[VB]
Dim conn As New MySql.Data.MySqlClient.MySqlConnection Dim myConnectionString as String myConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test;" Try conn.ConnectionString = myConnectionString conn.Open() Catch ex As MySql.Data.MySqlClient.MySqlException MessageBox.Show(ex.Message) End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; string myConnectionString; myConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { conn = new MySql.Data.MySqlClient.MySqlConnection(); conn.ConnectionString = myConnectionString; conn.Open(); } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show(ex.Message); }
You can also pass the connection string to the constructor of
the MySqlConnection
class:
[VB]
Dim myConnectionString as String myConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test;" Try Dim conn As New MySql.Data.MySqlClient.MySqlConnection(myConnectionString) conn.Open() Catch ex As MySql.Data.MySqlClient.MySqlException MessageBox.Show(ex.Message) End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; string myConnectionString; myConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { conn = new MySql.Data.MySqlClient.MySqlConnection(myConnectionString); conn.Open(); } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show(ex.Message); }
Once the connection is open it can be used by the other MySQL Connector/NET classes to communicate with the MySQL server.
Because connecting to an external server is unpredictable, it
is important to add error handling to your .NET application.
When there is an error connecting, the
MySqlConnection
class will return a
MySqlException
object. This object has two
properties that are of interest when handling errors:
Message
: A message that describes the
current exception.
Number
: The MySQL error number.
When handling errors, you can your application's response based on the error number. The two most common error numbers when connecting are as follows:
0
: Cannot connect to server.
1045
: Invalid username and/or password.
The following code shows how to adapt the application's response based on the actual error:
[VB]
Dim myConnectionString as String myConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test;" Try Dim conn As New MySql.Data.MySqlClient.MySqlConnection(myConnectionString) conn.Open() Catch ex As MySql.Data.MySqlClient.MySqlException Select Case ex.Number Case 0 MessageBox.Show("Cannot connect to server. Contact administrator") Case 1045 MessageBox.Show("Invalid username/password, please try again") End Select End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; string myConnectionString; myConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { conn = new MySql.Data.MySqlClient.MySqlConnection(myConnectionString); conn.Open(); } catch (MySql.Data.MySqlClient.MySqlException ex) { switch (ex.Number) { case 0: MessageBox.Show("Cannot connect to server. Contact administrator"); case 1045: MessageBox.Show("Invalid username/password, please try again"); } }
As of MySQL 4.1, it is possible to use prepared statements with MySQL Connector/NET. Use of prepared statements can provide significant performance improvements on queries that are executed more than once.
Prepared execution is faster than direct execution for statements executed more than once, primarily because the query is parsed only once. In the case of direct execution, the query is parsed every time it is executed. Prepared execution also can provide a reduction of network traffic because for each execution of the prepared statement, it is necessary only to send the data for the parameters.
Another advantage of prepared statements is that it uses a binary protocol that makes data transfer between client and server more efficient.
To prepare a statement, create a command object and set the
.CommandText
property to your query.
After entering your statement, call the
.Prepare
method of the
MySqlCommand
object. After the statement is
prepared, add parameters for each of the dynamic elements in
the query.
After you enter your query and enter parameters, execute the
statement using the .ExecuteNonQuery()
,
.ExecuteScalar()
, or
.ExecuteReader
methods.
For subsequent executions, you need only modify the values of
the parameters and call the execute method again, there is no
need to set the .CommandText
property or
redefine the parameters.
[VB]
Dim conn As New MySqlConnection Dim cmd As New MySqlCommand conn.ConnectionString = strConnection Try conn.Open() cmd.Connection = conn cmd.CommandText = "INSERT INTO myTable VALUES(NULL, ?number, ?text)" cmd.Prepare() cmd.Parameters.Add("?number", 1) cmd.Parameters.Add("?text", "One") For i = 1 To 1000 cmd.Parameters("?number").Value = i cmd.Parameters("?text").Value = "A string value" cmd.ExecuteNonQuery() Next Catch ex As MySqlException MessageBox.Show("Error " & ex.Number & " has occurred: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); conn.ConnectionString = strConnection; try { conn.Open(); cmd.Connection = conn; cmd.CommandText = "INSERT INTO myTable VALUES(NULL, ?number, ?text)"; cmd.Prepare(); cmd.Parameters.Add("?number", 1); cmd.Parameters.Add("?text", "One"); for (int i=1; i <= 1000; i++) { cmd.Parameters["?number"].Value = i; cmd.Parameters["?text"].Value = "A string value"; cmd.ExecuteNonQuery(); } } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); }
With the release of MySQL version 5 the MySQL server now supports stored procedures with the SQL 2003 stored procedure syntax.
A stored procedure is a set of SQL statements that can be stored in the server. Once this has been done, clients don't need to keep reissuing the individual statements but can refer to the stored procedure instead.
Stored procedures can be particularly useful in situations such as the following:
When multiple client applications are written in different languages or work on different platforms, but need to perform the same database operations.
When security is paramount. Banks, for example, use stored procedures for all common operations. This provides a consistent and secure environment, and procedures can ensure that each operation is properly logged. In such a setup, applications and users would not get any access to the database tables directly, but can only execute specific stored procedures.
MySQL Connector/NET supports the calling of stored procedures
through the MySqlCommand
object. Data can
be passed in and our of a MySQL stored procedure through use
of the MySqlCommand.Parameters
collection.
This section will not provide in-depth information on creating Stored Procedures. For such information, please refer to http://dev.mysql.com/doc/mysql/en/stored-procedures.html.
A sample application demonstrating how to use stored
procedures with MySQL Connector/NET can be found in the
Samples
directory of your MySQL Connector/NET
installation.
Stored procedures in MySQL can be created using a variety of
tools. First, stored procedures can be created using the
mysql command-line client. Second, stored
procedures can be created using the MySQL Query
Browser
GUI client. Finally, stored procedures can
be created using the .ExecuteNonQuery
method of the MySqlCommand
object:
[VB]
Dim conn As New MySqlConnection Dim cmd As New MySqlCommand conn.ConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test" Try conn.Open() cmd.Connection = conn cmd.CommandText = "CREATE PROCEDURE add_emp(" _ & "IN fname VARCHAR(20), IN lname VARCHAR(20), IN bday DATETIME, OUT empno INT) " _ & "BEGIN INSERT INTO emp(first_name, last_name, birthdate) " _ & "VALUES(fname, lname, DATE(bday)); SET empno = LAST_INSERT_ID(); END" cmd.ExecuteNonQuery() Catch ex As MySqlException MessageBox.Show("Error " & ex.Number & " has occurred: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); conn.ConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { conn.Open(); cmd.Connection = conn; cmd.CommandText = "CREATE PROCEDURE add_emp(" + "IN fname VARCHAR(20), IN lname VARCHAR(20), IN bday DATETIME, OUT empno INT) " + "BEGIN INSERT INTO emp(first_name, last_name, birthdate) " + "VALUES(fname, lname, DATE(bday)); SET empno = LAST_INSERT_ID(); END"; cmd.ExecuteNonQuery(); } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); }
It should be noted that, unlike the command-line and GUI clients, you are not required to specify a special delimiter when creating stored procedures in MySQL Connector/NET.
To call a stored procedure using MySQL Connector/NET, create a
MySqlCommand
object and pass the stored
procedure name as the .CommandText
property. Set the .CommandType
property to
CommandType.StoredProcedure
.
After the stored procedure is named, create one
MySqlCommand
parameter for every parameter
in the stored procedure. IN
parameters are
defined with the parameter name and the object containing the
value, OUT
parameters are defined with the
parameter name and the datatype that is expected to be
returned. All parameters need the parameter direction defined.
After defining parameters, call the stored procedure by using
the MySqlCommand.ExecuteNonQuery()
method:
[VB]
Dim conn As New MySqlConnection Dim cmd As New MySqlCommand conn.ConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test" Try conn.Open() cmd.Connection = conn cmd.CommandText = "add_emp" cmd.CommandType = CommandType.StoredProcedure cmd.Parameters.Add("?lname", 'Jones') cmd.Parameters("?lname").Direction = ParameterDirection.Input cmd.Parameters.Add("?fname", 'Tom') cmd.Parameters("?fname").Direction = ParameterDirection.Input cmd.Parameters.Add("?bday", #12/13/1977 2:17:36 PM#) cmd.Parameters("?bday").Direction = ParameterDirection.Input cmd.Parameters.Add("?empno", MySqlDbType.Int32) cmd.Parameters("?empno").Direction = ParameterDirection.Output cmd.ExecuteNonQuery() MessageBox.Show(cmd.Parameters("?empno").Value) Catch ex As MySqlException MessageBox.Show("Error " & ex.Number & " has occurred: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); conn.ConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { conn.Open(); cmd.Connection = conn; cmd.CommandText = "add_emp"; cmd.CommandType = CommandType.StoredProcedure; cmd.Parameters.Add("?lname", "Jones"); cmd.Parameters("?lname").Direction = ParameterDirection.Input; cmd.Parameters.Add("?fname", "Tom"); cmd.Parameters("?fname").Direction = ParameterDirection.Input; cmd.Parameters.Add("?bday", DateTime.Parse("12/13/1977 2:17:36 PM")); cmd.Parameters("?bday").Direction = ParameterDirection.Input; cmd.Parameters.Add("?empno", MySqlDbType.Int32); cmd.Parameters("?empno").Direction = ParameterDirection.Output; cmd.ExecuteNonQuery(); MessageBox.Show(cmd.Parameters("?empno").Value); } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); }
Once the stored procedure is called, the values of output
parameters can be retrieved by using the
.Value
property of the
MySqlConnector.Parameters
collection.
One common use for MySQL is the storage of binary data in
BLOB
columns. MySQL supports four different
BLOB datatypes: TINYBLOB
,
BLOB
, MEDIUMBLOB
, and
LONGBLOB
.
Data stored in a BLOB column can be accessed using Connector/NET and manipulated using client-side code. There are no special requirements for using Connector/NET with BLOB data.
Simple code examples will be presented within this section,
and a full sample application can be found in the
Samples
directory of the MySQL Connector/NET
installation.
The first step is using MySQL with BLOB data is to configure the server. Let's start by creating a table to be accessed. In my file tables, I usually have four columns: an AUTO_INCREMENT column of appropriate size (UNSIGNED SMALLINT) to serve as a primary key to identify the file, a VARCHAR column that stores the filename, an UNSIGNED MEDIUMINT column that stores the size of the file, and a MEDIUMBLOB column that stores the file itself. For this example, I will use the following table definition:
CREATE TABLE file( file_id SMALLINT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY, file_name VARCHAR(64) NOT NULL, file_size MEDIUMINT UNSIGNED NOT NULL, file MEDIUMBLOB NOT NULL);
After creating a table, you may need to modify the max_allowed_packet system variable. This variable determines how large of a packet (i.e. a single row) can be sent to the MySQL server. By default, the server will only accept a maximum size of 1 meg from our client application. If you do not intend to exceed 1 meg, this should be fine. If you do intend to exceed 1 meg in your file transfers, this number has to be increased.
The max_allowed_packet option can be modified using MySQL
Administrator's Startup Variables screen. Adjust the Maximum
allowed option in the Memory section of the Networking tab to
an appropriate setting. After adjusting the value, click the
Service Control
screen of
MySQL Administrator. You can also adjust this value directly
in the my.cnf file (add a line that reads
max_allowed_packet=xxM), or use the SET
max_allowed_packet=xxM; syntax from within MySQL.
Try to be conservative when setting max_allowed_packet, as transfers of BLOB data can take some time to complete. Try to set a value that will be adequate for your intended use and increase the value if necessary.
To write a file to a database we need to convert the file to a
byte array, then use the byte array as a parameter to an
INSERT
query.
The following code opens a file using a FileStream object,
reads it into a byte array, and inserts it into the
file
table:
[VB]
Dim conn As New MySqlConnection Dim cmd As New MySqlCommand Dim SQL As String Dim FileSize As UInt32 Dim rawData() As Byte Dim fs As FileStream conn.ConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test" Try fs = New FileStream("c:\image.png", FileMode.Open, FileAccess.Read) FileSize = fs.Length rawData = New Byte(FileSize) {} fs.Read(rawData, 0, FileSize) fs.Close() conn.Open() SQL = "INSERT INTO file VALUES(NULL, ?FileName, ?FileSize, ?File)" cmd.Connection = conn cmd.CommandText = SQL cmd.Parameters.Add("?FileName", strFileName) cmd.Parameters.Add("?FileSize", FileSize) cmd.Parameters.Add("?File", rawData) cmd.ExecuteNonQuery() MessageBox.Show("File Inserted into database successfully!", _ "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk) conn.Close() Catch ex As Exception MessageBox.Show("There was an error: " & ex.Message, "Error", _ MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); string SQL; UInt32 FileSize; byte[] rawData; FileStream fs; conn.ConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { fs = new FileStream(@"c:\image.png", FileMode.Open, FileAccess.Read); FileSize = fs.Length; rawData = new byte[FileSize]; fs.Read(rawData, 0, FileSize); fs.Close(); conn.Open(); SQL = "INSERT INTO file VALUES(NULL, ?FileName, ?FileSize, ?File)"; cmd.Connection = conn; cmd.CommandText = SQL; cmd.Parameters.Add("?FileName", strFileName); cmd.Parameters.Add("?FileSize", FileSize); cmd.Parameters.Add("?File", rawData); cmd.ExecuteNonQuery(); MessageBox.Show("File Inserted into database successfully!", "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk); conn.Close(); } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); }
The Read
method of the
FileStream
object is used to load the file
into a byte array which is sized according to the
Length
property of the FileStream object.
After assigning the byte array as a parameter of the
MySqlCommand
object, the
ExecuteNonQuery
method is called and the
BLOB is inserted into the file
table.
Once a file is loaded into the file
table,
we can use the MySqlDataReader
class to
retrieve it.
The following code retrieves a row from the
file
table, then loads the data into a
FileStream
object to be written to disk:
[VB]
Dim conn As New MySqlConnection Dim cmd As New MySqlCommand Dim myData As MySqlDataReader Dim SQL As String Dim rawData() As Byte Dim FileSize As UInt32 Dim fs As FileStream conn.ConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test" SQL = "SELECT file_name, file_size, file FROM file" Try conn.Open() cmd.Connection = conn cmd.CommandText = SQL myData = cmd.ExecuteReader If Not myData.HasRows Then Throw New Exception("There are no BLOBs to save") myData.Read() FileSize = myData.GetUInt32(myData.GetOrdinal("file_size")) rawData = New Byte(FileSize) {} myData.GetBytes(myData.GetOrdinal("file"), 0, rawData, 0, FileSize) fs = New FileStream("C:\newfile.png", FileMode.OpenOrCreate, FileAccess.Write) fs.Write(rawData, 0, FileSize) fs.Close() MessageBox.Show("File successfully written to disk!", "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk) myData.Close() conn.Close() Catch ex As Exception MessageBox.Show("There was an error: " & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; MySql.Data.MySqlClient.MySqlDataReader myData; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); string SQL; UInt32 FileSize; byte[] rawData; FileStream fs; conn.ConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; SQL = "SELECT file_name, file_size, file FROM file"; try { conn.Open(); cmd.Connection = conn; cmd.CommandText = SQL; myData = cmd.ExecuteReader(); if (! myData.HasRows) throw new Exception("There are no BLOBs to save"); myData.Read(); FileSize = myData.GetUInt32(myData.GetOrdinal("file_size")); rawData = new byte[FileSize]; myData.GetBytes(myData.GetOrdinal("file"), 0, rawData, 0, FileSize); fs = new FileStream(@"C:\newfile.png", FileMode.OpenOrCreate, FileAccess.Write); fs.Write(rawData, 0, FileSize); fs.Close(); MessageBox.Show("File successfully written to disk!", "Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk); myData.Close(); conn.Close(); } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show("Error " + ex.Number + " has occurred: " + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); }
After connecting, the contents of the file
table are loaded into a MySqlDataReader
object. The GetBytes
method of the
MySqlDataReader is used to load the BLOB into a byte array,
which is then written to disk using a FileStream object.
The GetOrdinal
method of the
MySqlDataReader can be used to determine the integer index of
a named column. Use of the GetOrdinal method prevents errors
if the column order of the SELECT query is changed.
Crystal Reports is a common tool used by Windows application developers to perform reporting and document generation. In this section we will show how to use Crystal Reports XI with MySQL and Connector/NET.
Complete sample applications are available in the CrystalDemo subdirectory of the Samples directory of your MySQL Connector/NET installation.
When creating a report in Crystal Reports there are two options for accessing the MySQL data while designing your report.
The first option is to use Connector/ODBC as an ADO data source when designing your report. You will be able to browse your database and choose tables and fields using drag and drop to build your report. The disadvantage of this approach is that additional work must be performed within your application to produce a dataset that matches the one expected by your report.
The second option is to create a dataset in VB.NET and save it as XML. This XML file can then be used to design a report. This works quite well when displaying the report in your application, but is less versatile at design time because you must choose all relevant columns when creating the dataset. If you forget a column you must re-create the dataset before the column can be added to the report.
The following code can be used to create a dataset from a query and write it to disk:
[VB]
Dim myData As New DataSet Dim conn As New MySqlConnection Dim cmd As New MySqlCommand Dim myAdapter As New MySqlDataAdapter conn.ConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=world" Try conn.Open() cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " _ & "country.name, country.population, country.continent " _ & "FROM country, city ORDER BY country.continent, country.name" cmd.Connection = conn myAdapter.SelectCommand = cmd myAdapter.Fill(myData) myData.WriteXml("C:\dataset.xml", XmlWriteMode.WriteSchema) Catch ex As Exception MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
DataSet myData = new DataSet(); MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; MySql.Data.MySqlClient.MySqlDataAdapter myAdapter; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); myAdapter = new MySql.Data.MySqlClient.MySqlDataAdapter(); conn.ConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " + "country.name, country.population, country.continent " + "FROM country, city ORDER BY country.continent, country.name"; cmd.Connection = conn; myAdapter.SelectCommand = cmd; myAdapter.Fill(myData); myData.WriteXml(@"C:\dataset.xml", XmlWriteMode.WriteSchema); } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error); }
The resulting XML file can be used as an ADO.NET XML datasource when designing your report.
If you choose to design your reports using Connector/ODBC, it can be downloaded from dev.mysql.com.
For most purposes the Standard Report wizard should help with the initial creation of a report. To start the wizard, open Crystal Reports and choose the New > Standard Report option from the File menu.
The wizard will first prompt you for a data source. If you are using Connector/ODBC as your data source, use the OLEDB provider for ODBC option from the OLE DB (ADO) tree instead of the ODBC (RDO) tree when choosing a data source. If using a saved dataset, choose the ADO.NET (XML) option and browse to your saved dataset.
The remainder of the report creation process is done automatically by the wizard.
After the report is created, choose the Report Options... entry of the File menu. Un-check the Save Data With Report option. This prevents saved data from interfering with the loading of data within our application.
To display a report we first populate a dataset with the data needed for the report, then load the report and bind it to the dataset. Finally we pass the report to the crViewer control for display to the user.
The following references are needed in a project that displays a report:
CrytalDecisions.CrystalReports.Engine
CrystalDecisions.ReportSource
CrystalDecisions.Shared
CrystalDecisions.Windows.Forms
The following code assumes that you created your report using
a dataset saved using the code shown in
Creating a
Data Source and have a crViewer control on your form
named myViewer
.
[VB]
Imports CrystalDecisions.CrystalReports.Engine Imports System.Data Imports MySql.Data.MySqlClient Dim myReport As New ReportDocument Dim myData As New DataSet Dim conn As New MySqlConnection Dim cmd As New MySqlCommand Dim myAdapter As New MySqlDataAdapter conn.ConnectionString = _ "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=test" Try conn.Open() cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " _ & "country.name, country.population, country.continent " _ & "FROM country, city ORDER BY country.continent, country.name" cmd.Connection = conn myAdapter.SelectCommand = cmd myAdapter.Fill(myData) myReport.Load(".\world_report.rpt") myReport.SetDataSource(myData) myViewer.ReportSource = myReport Catch ex As Exception MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
using CrystalDecisions.CrystalReports.Engine; using System.Data; using MySql.Data.MySqlClient; ReportDocument myReport = new ReportDocument(); DataSet myData = new DataSet(); MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; MySql.Data.MySqlClient.MySqlDataAdapter myAdapter; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); myAdapter = new MySql.Data.MySqlClient.MySqlDataAdapter(); conn.ConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { cmd.CommandText = "SELECT city.name AS cityName, city.population AS CityPopulation, " + "country.name, country.population, country.continent " + "FROM country, city ORDER BY country.continent, country.name"; cmd.Connection = conn; myAdapter.SelectCommand = cmd; myAdapter.Fill(myData); myReport.Load(@".\world_report.rpt"); myReport.SetDataSource(myData); myViewer.ReportSource = myReport; } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error); }
A new dataset it generated using the same query used to generate the previously saved dataset. Once the dataset is filled, a ReportDocument is used to load the report file and bind it to the dataset. The ReportDocument is the passed as the ReportSource of the crViewer.
This same approach is taken when a report is created from a single table using Connector/ODBC. The dataset replaces the table used in the report and the report is displayed properly.
When a report is created from multiple tables using Connector/ODBC, a dataset with multiple tables must be created in our application. This allows each table in the report data source to be replaced with a report in the dataset.
We populate a dataset with multiple tables by providing multiple SELECT statements in our MySqlCommand object. These SELECT statements are based on the SQL query shown in Crystal Reports in the Database menu's Show SQL Query option. Assume the following query:
SELECT `country`.`Name`, `country`.`Continent`, `country`.`Population`, `city`.`Name`, `city`.`Population` FROM `world`.`country` `country` LEFT OUTER JOIN `world`.`city` `city` ON `country`.`Code`=`city`.`CountryCode` ORDER BY `country`.`Continent`, `country`.`Name`, `city`.`Name`
This query is converted to two SELECT queries and displayed with the following code:
[VB]
Imports CrystalDecisions.CrystalReports.Engine Imports System.Data Imports MySql.Data.MySqlClient Dim myReport As New ReportDocument Dim myData As New DataSet Dim conn As New MySqlConnection Dim cmd As New MySqlCommand Dim myAdapter As New MySqlDataAdapter conn.ConnectionString = "server=127.0.0.1;" _ & "uid=root;" _ & "pwd=12345;" _ & "database=world" Try conn.Open() cmd.CommandText = "SELECT name, population, countrycode FROM city ORDER BY countrycode, name; " _ & "SELECT name, population, code, continent FROM country ORDER BY continent, name" cmd.Connection = conn myAdapter.SelectCommand = cmd myAdapter.Fill(myData) myReport.Load(".\world_report.rpt") myReport.Database.Tables(0).SetDataSource(myData.Tables(0)) myReport.Database.Tables(1).SetDataSource(myData.Tables(1)) myViewer.ReportSource = myReport Catch ex As Exception MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try
[C#]
using CrystalDecisions.CrystalReports.Engine; using System.Data; using MySql.Data.MySqlClient; ReportDocument myReport = new ReportDocument(); DataSet myData = new DataSet(); MySql.Data.MySqlClient.MySqlConnection conn; MySql.Data.MySqlClient.MySqlCommand cmd; MySql.Data.MySqlClient.MySqlDataAdapter myAdapter; conn = new MySql.Data.MySqlClient.MySqlConnection(); cmd = new MySql.Data.MySqlClient.MySqlCommand(); myAdapter = new MySql.Data.MySqlClient.MySqlDataAdapter(); conn.ConnectionString = "server=127.0.0.1;uid=root;" + "pwd=12345;database=test;"; try { cmd.CommandText = "SELECT name, population, countrycode FROM city ORDER " + "BY countrycode, name; SELECT name, population, code, continent FROM " + "country ORDER BY continent, name"; cmd.Connection = conn; myAdapter.SelectCommand = cmd; myAdapter.Fill(myData); myReport.Load(@".\world_report.rpt"); myReport.Database.Tables(0).SetDataSource(myData.Tables(0)); myReport.Database.Tables(1).SetDataSource(myData.Tables(1)); myViewer.ReportSource = myReport; } catch (MySql.Data.MySqlClient.MySqlException ex) { MessageBox.Show(ex.Message, "Report could not be created", MessageBoxButtons.OK, MessageBoxIcon.Error); }
It is important to order the SELECT queries in alphabetical order, as this is the order the report will expect its source tables to be in. One SetDataSource statement is needed for each table in the report.
This approach can cause performance problems because Crystal Reports must bind the tables together on the client-side, which will be slower than using a pre-saved dataset.
MySQL and the .NET languages handle date and time information
differently, with MySQL allowing dates that cannot be
represented by a .NET data type, such as '0000-00-00
00:00:00
'. These differences can cause problems if
not properly handled.
In this section we will demonstrate how to properly handle date and time information when using MySQL Connector/NET.
The differences in date handling can cause problems for
developers who use invalid dates. Invalid MySQL dates cannot
be loaded into native .NET DateTime
objects, including NULL
dates.
Because of this issue, .NET DataSet
objects
cannot be populated by the Fill
method of
the MySqlDataAdapter
class as invalid dates
will cause a
System.ArgumentOutOfRangeException
exception to occur.
The best solution to the date problem is to restrict users from entering invalid dates. This can be done on either the client or the server side.
Restricting invalid dates on the client side is as simple as
always using the .NET DateTime
class to
handle dates. The DateTime
class will only
allow valid dates, ensuring that the values in your database
are also valid. The disadvantage of this is that it is not
useful in a mixed environment where .NET and non .NET code are
used to manipulate the database, as each application must
perform its own date validation.
Users of MySQL 5.0.2 and higher can use the new
traditional
SQL mode to restrict invalid
date values. For information on using the
traditional
SQL mode, see
Section 5.3.2, “The Server SQL Mode”.
Although it is strongly recommended that you avoid the use of
invalid dates within your .NET application, it is possible to
use invalid dates by means of the
MySqlDateTime
datatype.
The MySqlDateTime
datatype supports the
same date values that are supported by the MySQL server. The
default behavior of MySQL Connector/NET is to return a .NET
DateTime object for valid date values, and return an error for
invalid dates. This default can be modified to cause
MySQL Connector/NET to return MySqlDateTime
objects for invalid dates.
To instruct MySQL Connector/NET to return a
MySqlDateTime
object for invalid dates, add
the following line to your connection string:
Allow Zero Datetime=True
Please note that the use of the
MySqlDateTime
class can still be
problematic. The following are some known issues:
Data binding for invalid dates can still cause errors (zero dates like 0000-00-00 do not seem to have this problem).
The ToString
method return a date
formatted in the standard MySQL format (for example,
2005-02-23 08:50:25
). This differs from
the ToString
behavior of the .NET
DateTime class.
The MySqlDateTime
class supports NULL
dates, while the .NET DateTime class does not. This can
cause errors when trying to convert a MySQLDateTime to a
DateTime if you do not check for NULL first.
Because of the known issues, the best recommendation is still to use only valid dates in your application.
The .NET DateTime
datatype cannot handle
NULL
values. As such, when assigning values
from a query to a DateTime
variable, you
must first check whether the value is in fact
NULL
.
When using a MySqlDataReader
, use the
.IsDBNull
method to check whether a value
is NULL
before making the assignment:
[VB]
If Not myReader.IsDBNull(myReader.GetOrdinal("mytime")) Then myTime = myReader.GetDateTime(myReader.GetOrdinal("mytime")) Else myTime = DateTime.MinValue End If
[C#]
if (! myReader.IsDBNull(myReader.GetOrdinal("mytime"))) myTime = myReader.GetDateTime(myReader.GetOrdinal("mytime")); else myTime = DateTime.MinValue;
NULL
values will work in a dataset and can
be bound to form controls without special handling.
The parameter collection object's Add()
method added parameters to the list without first checking to
see whether they already existed. Now it updates the value of
the existing parameter object if it exists. (Bug #13927)
A #42000Query was empty
exception occurred
when executing a query built with
MySqlCommandBuilder
, if the query string
ended with a semicolon. (Bug #14631)
Implemented the
MySqlCommandBuilder.DeriveParameters
method
that is used to discover the parameters for a stored
procedure. (Bug #13632)
Added support for the cp932
character set.
(Bug #13806)
Calling a stored procedure where a parameter contained special
characters (such as '@'
) would produce an
exception. Note that ANSI_QUOTES
had to be
enabled to make this possible. (Bug #13753)
A statement that contained multiple references to the same parameter could not be prepared. (Bug #13541)
The Ping()
method did not update the
State
property of the
Connection
object. (Bug #13658)
The nant
build sequence had problems. (Bug
#12978)
Serializing a parameter failed if the first value passed in
was NULL
. (Bug #13276)
Field names that contained the following characters caused
errors: ()%<>/
(Bug #13036)
The MySQL Connector/NET 1.0.5 installer would not install alongside MySQL Connector/NET 1.0.4. (Bug #12835)
MySQL Connector/NET 1.0.5 could not connect on Mono. (Bug #13345)
With multiple hosts in the connection string, MySQL Connector/NET would not connect to the last host in the list. (Bug #12628)
MySQL Connector/NET interpreted the new decimal data type as a byte array. (Bug #11294)
The cp1250
character set was not supported.
(Bug #11621)
Connection could fail when .NET thread pool had no available worker threads. (Bug #10637)
Decimal parameters caused syntax errors. (Bug #11550, Bug #10486, Bug #10152)
A call to a stored procedure caused an exception if the stored procedure had no parameters. (Bug #11542)
Certain malformed queries would trigger a Connection
must be valid and open
error message. (Bug #11490)
The MySqlCommandBuilder
class could not
handle queries that referenced tables in a database other than
the default database. (Bug #8382)
MySQL Connector/NET could not work properly with certain regional settings. (WL#8228)
Trying to use a stored procedure when
Connection.Database
was not populated
generated an exception. (Bug #11450)
Trying to read a TIMESTAMP
column generated
an exception. (Bug #7951)
Parameters were not recognized when they were separated by linefeeds. (Bug #9722)
Calling MySqlConnection.clone
when a
connection string had not yet been set on the original
connection would generate an error. (Bug #10281)
Added support to call a stored function from MySQL Connector/NET. (Bug #10644)
MySQL Connector/NET could not connect to MySQL 4.1.14. (Bug #12771)
The ConnectionString
property could not be
set when a MySqlConnection
object was added
with the designer. (Bug #12551, Bug #8724)
Bug #7243 calling prepare causing exception [fixed]
Fixed another small problem with prepared statements
Bug #7258 MySqlCommand.Connection returns an IDbConnection [fixed]
Bug #7345 MySqlAdapter.Fill method throws Error message : Non-negative number required [fixed]
Bug #7478 Clone method bug in MySqlCommand [fixed]
Bug #7612 MySqlDataReader.GetString(index) returns non-Null value when field is Null [fixed]
Bug #7755 MySqlReader.GetInt32 throws exception if column is unsigned [fixed]
Bug #7704 GetBytes is working no more [fixed]
Bug #7724 Quote character \222 not quoted in EscapeString [fixed]
Fixed problem that causes named pipes to not work with some blob functionality
Fixed problem with shared memory connections
Bug #7436 Problem with Multiple resultsets... [fixed]
Added or filled out several more topics in the API reference documentation
Made MySQL the default named pipe name
Now SHOW COLLATION is used upon connection to retrieve the full list of charset ids
Fixed Invalid character set index: 200 (Bug #6547)
Installer now includes options to install into GAC and create Start Menu items
Bug #6863 - Int64 Support in MySqlCommand Parameters [fixed]
Connections now do not have to give a database on the connection string
Bug #6770 - MySqlDataReader.GetChar(int i) throws IndexOutOfRange Exception [fixed]
Fixed problem where multiple resultsets having different numbers of columns would cause a problem
Bug #6983 Exception stack trace lost when re-throwing exceptions [fixed]
Fixed major problem with detecting null values when using prepared statements
Bug #6902 Errors in parsing stored procedure parameters [fixed]
Bug #6668 Integer "out" parameter from stored procedure returned as string [fixed]
Bug #7032 MySqlDateTime in Datatables sorting by Text, not Date. [fixed]
Bug #7133 Invalid query string when using inout parameters [fixed]
Bug #6831 Test suite fails with MySQL 4.0 because of case sensitivity of table names [fixed]
Bug #7132 Inserting DateTime causes System.InvalidCastException to be thrown [fixed]
Bug #6879 InvalidCast when using DATE_ADD-function [fixed]
Bug #6634 An Open Connection has been Closed by the Host System [fixed]
Added ServerThread property to MySqlConnection to expose server thread id
Added Ping method to MySqlConnection
Changed the name of the test suite to MySql.Data.Tests.dll
Fixed problem with MySqlBinary where string values could not be used to update extended text columns
Fixed Installation directory ignored using custom installation (Bug #6329)
Fixed problem where setting command text leaves the command in a prepared state
Fixed double type handling in MySqlParameter(string parameterName, object value) (Bug #6428)
Fixed Zero date "0000-00-00" is returned wrong when filling Dataset (Bug #6429)
Fixed problem where calling stored procedures might cause an "Illegal mix of collations" problem.
Added charset connection string option
Fixed #HY000 Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (utf8_general_ (Bug #6322)
Added the TableEditor CS and VB sample
Fixed Charset-map for UCS-2 (Bug #6541)
Updated the installer to include the new samples
Fixed Long inserts take very long time (Bu #5453)
Fixed Objects not being disposed (Bug #6649)
Provider is now using character set specified by server as default
Fixed BUG #5602 Possible bug in MySqlParameter(string, object) constructor
Fixed BUG #5458 Calling GetChars on a longtext column throws an exception
Fixed BUG #5474 cannot run a stored procedure populating mysqlcommand.parameters
Fixed BUG #5469 Setting DbType throws NullReferenceException
Fixed problem where connector was not issuing a CMD_QUIT before closing the socket
Fixed BUG #5392 MySqlCommand sees "?" as parameters in string literals
Fixed problem with ConnectionInternal where a key might be added more than once
CP1252 is now used for Latin1 only when the server is 4.1.2 and later
Fixed BUG #5388 DataReader reports all rows as NULL if one row is NULL
Virtualized driver subsystem so future releases could easily support client or embedded server support
Field buffers being reused to decrease memory allocations and increase speed
Fixed problem where using old syntax while using the interfaces caused problems
Using PacketWriter instead of Packet for writing to streams
Refactored compression code into CompressedStream to clean up NativeDriver
Added test case for resetting the command text on a prepared command
Fixed problem where MySqlParameterCollection.Add() would throw unclear exception when given a null value (Bug #5621)
Fixed construtor initialize problems in MySqlCommand() (Bug #5613)
Fixed Parsing the ';' char (Bug #5876)
Fixed missing Reference in DbType setter (Bug #5897)
Fixed System.OverflowException when using YEAR datatype (Bug #6036)
Added Aggregate function test (wasn't really a bug)
Fixed serializing of floating point parameters (double, numeric, single, decimal) (Bug #5900)
IsNullable error (Bug #5796)
Fixed problem where connection lifetime on the connect string was not being respected
Fixed problem where Min Pool Size was not being respected
Fixed MySqlDataReader and 'show tables from ...' behavior (Bug #5256)
Implemented SequentialAccess
Fixed MySqlDateTime sets IsZero property on all subseq.records after first zero found (Bug #6006)
Fixed Can't display Chinese correctly (Bug #5288)
Fixed Russian character support as well
Fixed Method TokenizeSql() uses only a limited set of valid characters for parameters (Bug #6217)
Fixed NET Connector source missing resx files (Bug #6216)
Fixed DBNull Values causing problems with retrieving/updating queries. (Bug #5798)
Fixed Yet Another "object reference not set to an instance of an object" (Bug #5496)
Fixed problem in PacketReader where it could try to allocate the wrong buffer size in EnsureCapacity
Fixed GetBoolean returns wrong values (Bug #6227)
Fixed IndexOutOfBounds when reading BLOB with DataReader with GetString(index) (Bug #6230)
Fixed BUG# 3889 Thai encoding not correctly supported
Updated many of the test cases
Fixed problem with using compression
Bumped version number to 1.0.0 for beta 1 release
Added COPYING.rtf file for use in installer
Removed all of the XML comment warnings (I'll clean them up better later)
Removed some last references to ByteFX
Added test fixture for prepared statements
All type classes now implement a SerializeBinary method for sending their data to a PacketWriter
Added PacketWriter class that will enable future low-memory large object handling
Fixed many small bugs in running prepared statements and stored procedures
Changed command so that an exception will not be throw in executing a stored procedure with parameters in old syntax mode
SingleRow behavior now working right even with limit
GetBytes now only works on binary columns
Logger now truncates long sql commands so blob columns don't blow out our log
host and database now have a default value of "" unless otherwise set
FIXED BUG# 5214 Connection Timeout seems to be ignored
Added test case for bug# 5051: GetSchema not working correctly
Fixed problem where GetSchema would return false for IsUnique when the column is key
MySqlDataReader GetXXX methods now using the field level MySqlValue object and not performing conversions
FIXED BUG# 5097: DataReader returning NULL for time column
Added test case for LOAD DATA LOCAL INFILE
Added replacetext custom nant task
Added CommandBuilderTest fixture
Added Last One Wins feature to CommandBuilder
Fixed persist security info case problem
Fixed GetBool so that 1, true, "true", and "yes" all count as trueWL# 2024 Make parameter mark configurable
Added the "old syntax" connection string parameter to allow use of @ parameter marker
Fixed Bug #4658 MySqlCommandBuilder
Fixed Bug #4864 ByteFX.MySqlClient caches passwords if 'Persist Security Info' is false
Updated license banner in all source files to include FLOSS exception
Added new .Types namespace and implementations for most current MySql types
Added MySqlField41 as a subclass of MySqlField
Changed many classes to now use the new .Types types
Changed type enum int to Int32, short to Int16, and bigint to Int64
Added dummy types UInt16, UInt32, and UInt64 to allow an unsigned parameter to be made
Connections are now reset when they are pulled from the connection pool
Refactored auth code in driver so it can be used for both auth and reset
Added UserReset test in PoolingTests.cs
Connections are now reset using COM_CHANGE_USER when pulled from the pool
Implemented SingleResultSet behavior
Implemented support of unicode
Added char set mappings for utf-8 and ucs-2
fixed Bug #4520 time fields overflow using bytefx .net mysql driver
Modified time test in data type test fixture to check for time spans where hours > 24
Fixed Bug #4505 Wrong string with backslash escaping in ByteFx.Data.MySqlClient.MySqlParameter
Added code to Parameter test case TestQuoting to test for backslashes
Fixed Bug #4486 mysqlcommandbuilder fails with multi-word column names
Fixed bug in TokenizeSql where underscore would terminate character capture in parameter name
Added test case for spaces in column names
Fixed bug# 4324 - MySqlDataReader.GetBytes don't works correctly
Added GetBytes() test case to DataReader test fixture
Now reading all server variables in InternalConnection.Configure into Hashtable
Now using string[] for index map in CharSetMap
Added CRInSQL test case for carriage returns in SQL
setting maxPacketSize to default value in Driver.ctor
Fixed bug #4442 - Setting MySqlDbType on a parameter doesn't set generic type
Removed obsolete data types Long and LongLong
Fixed bug# 4071 - Overflow exception thrown when using "use pipe" on connection string
Changed "use pipe" keyword to "pipe name" or just "pipe"
Allow reading multiple resultsets from a single query
Added flags attribute to ServerStatusFlags enum
Changed name of ServerStatus enum to ServerStatusFlags
Fixed BUG #4386 - Inserted data row doesn't update properly
Fixed bug #4074 - Error processing show create table
Change Packet.ReadLenInteger to ReadPackedLong and added packet.ReadPackedInteger that alwasy reads integers packed with 2,3,4
Added syntax.cs test fixture to test various SQL syntax bugs
Fixed bug# 4149 Improper handling of time values. Now time value of 00:00:00 is not treated as null.
Moved all test suite files into TestSuite folder
Fixed bug where null column would move the result packet pointer backward
Added new nant build script
Fixed BUG #3917 - clear tablename so it will be regen'ed properly during the next GenerateSchema.
Fixed bug #3915 - GetValues was always returning zero and was also always trying to copy all fields rather than respecting the size of the array passed in.
Implemented shared memory access protocol
Implemented prepared statements for MySQL 4.1
Implemented stored procedures for MySQL 5.0
Renamed MySqlInternalConnection to InternalConnection
SQL is now parsed as chars, fixes problems with other languages
Added logging and allow batch connection string options
Fixed bug #3888 - RowUpdating event not set when setting the DataAdapter property
Fixed bug in char set mapping
Implemented 4.1 authentication
Improved open/auth code in driver
Improved how connection bits are set during connection
Database name is now passed to server during initial handshake
Changed namespace for client to MySql.Data.MySqlClient
Changed assembly name of client to MySql.Data.dll
Changed license text in all source files to GPL
Added the MySqlClient.build Nant file
Removed the mono batch files
Moved some of the unused files into notused folder so nant build file can use wildcards
Implemented shared memory accesss
Major revamp in code structure
Prepared statements now working for MySql 4.1.1 and later
Finished implementing auth for 4.0, 4.1.0, and 4.1.1
Changed namespace from MySQL.Data.MySQLClient back to MySql.Data.MySqlClient
Fixed bug in CharSetMapping where it was trying to use text names as ints
Changed namespace to MySQL.Data.MySQLClient
Integrated auth changes from UC2004
Fixed bug where calling any of the GetXXX methods on a datareader before or after reading data would not throw the appropriate exception (thanks Luca Morelli <[email protected]>)
Added TimeSpan code in parameter.cs to properly serialize a timespan object to mysql time format (thanks Gianluca Colombo <[email protected]>)
Added TimeStamp to parameter serialization code. Prevented DataAdatper updates from working right (thanks MIchael King)
Fixed a misspelling in MySqlHelper.cs (thanks Patrick Kristiansen)
Driver now using charset number given in handshake to create encoding
Changed command editor to point to MySqlClient.Design
Fixed bug in Version.isAtLeast
Changed DBConnectionString to support changes done to MySqlConnectionString
Removed SqlCommandEditor and DataAdapterPreviewDialog
Using new long return values in many places
Integrated new CompressedStream class
Changed ConnectionString and added attributes to allow it to be used in MySqlClient.Design
Changed packet.cs to support newer lengths in ReadLenInteger
changed other classes to use new properties and fields of MySqlConnectionString
ConnectionInternal is now using PING to see whether the server is alive
Moved toolbox bitmaps into resource/
Changed field.cs to allow values to come directly from row buffer
Changed to use the new driver.Send syntax
Using a new packet queueing system
started work handling the "broken" compression packet handling
Fixed bug in StreamCreator where failure to connect to a host would continue to loop infinitly (thanks Kevin Casella)
Improved connectstring handling
Moved designers into Pro product
Removed some old commented out code from command.cs
Fixed a problem with compression
Fixed connection object where an exception throw prior to the connection opening would not leave the connection in the connecting state (thanks Chris Cline )
Added GUID support
Fixed sequence out of order bug (thanks Mark Reay)
Enum values now supported as parameter values (thanks Philipp Sumi)
Year datatype now supported
fixed compression
Fixed bug where a parameter with a TimeSpan as the value would not serialize properly
Fixed bug where default ctor would not set default connection string values
Added some XML comments to some members
Work to fix/improve compression handling
Improved ConnectionString handling so that it better matches the standard set by SqlClient.
A MySqlException is now thrown if a username is not included in the connection string
Localhost is now used as the default if not specified on the connection string
An exception is now thrown if an attempt is made to set the connection string while the connection is open
Small changes to ConnectionString docs
Removed MultiHostStream and MySqlStream. Replaced it with Common/StreamCreator
Added support for Use Pipe connection string value
Added Platform class for easier access to platform utility functions
Fixed small pooling bug where new connection was not getting created after IsAlive fails
Added Platform.cs and StreamCreator.cs
Fixed Field.cs to properly handle 4.1 style timestamps
Changed Common.Version to Common.DBVersion to avoid name conflict
Fixed field.cs so that text columns return the right field type (thanks [email protected])
Added MySqlError class to provide some reference for error codes (thanks Geert Veenstra)
Added Unix socket support (thanks Mohammad DAMT [[email protected]])
only calling Thread.Sleep when no data is available
improved escaping of quote characters in parameter data
removed misleading comments from parameter.cs
fixed pooling bug
same pooling bug fixed again!! ;-)
Fixed ConnectionSTring editor dialog (thanks marco p (pomarc))
UserId now supported in connection strings (thanks Jeff Neeley)
Attempting to create a parameter that is not input throws an exception (thanks Ryan Gregg)
Added much documentation
checked in new MultiHostStream capability. Big thanks to Dan Guisinger for this. he originally submitted the code and idea of supporting multiple machines on the connect string.
Added alot of documentation. Still alot to do.
Fixed speed issue with 0.73
changed to Thread.Sleep(0) in MySqlDataStream to help optimize the case where it doesn't need to wait (thanks Todd German)
Prepopulating the idlepools to MinPoolSize
Fixed MySqlPool deadlock condition as well as stupid bug where CreateNewPooledConnection was not ever adding new connections to the pool. Also fixed MySqlStream.ReadBytes and ReadByte to not use TicksPerSecond which does not appear to always be right. (thanks Matthew J. Peddlesden)
Fix for precision and scale (thanks Matthew J. Peddlesden)
Added Thread.Sleep(1) to stream reading methods to be more cpu friendly (thanks Sean McGinnis)
Fixed problem where ExecuteReader would sometime return null (thanks Lloyd Dupont )
Fixed major bug with null field handling (thanks Naucki)
enclosed queries for max_allowed_packet and characterset inside try catch (and set defaults)
fixed problem where socket was not getting closed properly (thanks Steve!)
Fixed problem where ExecuteNonQuery was not always returning the right value
Fixed InternalConnection to not use @@session.max_allowed_packet but use @@max_allowed_packet. (Thanks Miguel)
Added many new XML doc lines
Fixed sql parsing to not send empty queries (thanks Rory)
Fixed problem where the reader was not unpeeking the packet on close
Fixed problem where user variables were not being handled (thanks Sami Vaaraniemi)
Fixed loop checking in the MySqlPool (thanks Steve M. Brown)
Fixed ParameterCollection.Add method to match SqlClient (thanks Joshua Mouch)
Fixed ConnectionSTring parsing to handle no and yes for boolean and not lowercase values (thanks Naucki)
Added InternalConnection class, changes to pooling
Implemented Persist Security Info
Added security.cs and version.cs to project
Fixed DateTime handling in Parameter.cs (thanks Burkhard Perkens-Golomb)
Fixed parameter serialization where some types would throw a cast exception
Fixed DataReader to convert all returned values to prevent casting errors (thanks Keith Murray)
Added code to Command.ExecuteReader to return null if the initial SQL command throws an exception (thanks Burkhard Perkens-Golomb)
Fixed ExecuteScalar bug introduced with restructure
Restructure to allow for LOCAL DATA INFILE and better sequencing of packets
Fixed several bugs related to restructure.
Early work done to support more secure passwords in Mysql 4.1. Old passwords in 4.1 not supported yet
Parameters appearing after system parameters are now handled correctly (Adam M. (adammil))
strings can now be assigned directly to blob fields (Adam M.)
Fixed float parameters (thanks Pent)
Improved Parameter ctor and ParameterCollection.Add methods to better match SqlClient (thx Joshua Mouch )
Corrected Connection.CreateCommand to return a MySqlCommand type
Fixed connection string designer dialog box problem (thanks Abraham Guyt)
Fixed problem with sending commands not always reading the response packet (thanks Joshua Mouch )
Fixed parameter serialization where some blobs types were not being handled (thanks Sean McGinnis )
Removed spurious MessageBox.show from DataReader code (thanks Joshua Mouch )
Fixed a nasty bug in the split sql code (thanks everyone! :-) )
Fixed bug in MySqlStream where too much data could attempt to be read (thanks Peter Belbin)
Implemented HasRows (thanks Nash Pherson)
Fixed bug where tables with more than 252 columns cause an exception ( thanks Joshua Kessler )
Fixed bug where SQL statements ending in ; would cause a problem ( thanks Shane Krueger )
Fixed bug in driver where error messages were getting truncated by 1 character (thanks Shane Krueger)
Made MySqlException serializable (thanks Mathias Hasselmann)
Updated some of the character code pages to be more accurate
Fixed problem where readers could be opened on connections that had readers open
Release of 0.70
Moved test to separate assembly MySqlClientTests
Fixed stupid problem in driver with sequence out of order (Thanks Peter Belbin)
Added some pipe tests
Increased default max pool size to 50
Compiles with Mono 0-24
Fixed connection and data reader dispose problems
Added String datatype handling to parameter serialization
Fixed sequence problem in driver that occurred after thrown exception (thanks Burkhard Perkens-Golomb)
Added support for CommandBehavior.SingleRow to DataReader
Fixed command sql processing so quotes are better handled (thanks Theo Spears)
Fixed parsing of double, single, and decimal values to account for non-English separators. You still have to use the right syntax if you using hard coded sql, but if you use parameters the code will convert floating point types to use '.' appropriately internal both into the server and out. [ Thanks anonymous ]
Added MySqlStream class to simplify timeOuts and driver coding.
Fixed DataReader so that it is closed properly when the associated connection is closed. [thanks smishra]
Made client more SqlClient compliant so that DataReaders have to be closed before the connection can be used to run another command
Improved DBNull.Value handling in the fields
Added several unit tests
Fixed MySqlException so that the base class is actually called :-o
Improved driver coding
Fixed bug where NextResult was returning false on the last resultset
Added more tests for MySQL
Improved casting problems by equating unsigned 32bit values to Int64 and usigned 16bit values to Int32, and so forth.
Added new ctor for MySqlParameter for (name, type, size, srccol)
Fixed bug in MySqlDataReader where it didn't check for null fieldlist before returning field count
Started adding MySqlClient unit tests (added MySqlClient/Tests folder and some test cases)
Fixed some things in Connection String handling
Moved INIT_DB to MySqlPool. I may move it again, this is in preparation of the conference.
Fixed bug inside CommandBuilder that prevented inserts from happening properly
Reworked some of the internals so that all three execute methods of Command worked properly
FIxed many small bugs found during benchmarking
The first cut of CoonectionPooling is working. "min pool size" and "max pool size" are respected.
Work to enable multiple resultsets to be returned
Character sets are handled much more intelligently now. The driver queries MySQL at startup for the default character set. That character set is then used for conversions if that code page can be loaded. If not, then the default code page for the current OS is used.
Added code to save the inferred type in the name,value ctor of Parameter
Also, inferred type if value of null parameter is changed using Value property
Converted all files to use proper Camel case. MySQL is now MySql in all files. PgSQL is now PgSql
Added attribute to PgSql code to prevent designer from trying to show
Added MySQLDbType property to Parameter object and added proper conversion code to convert from DbType to MySQLDbType)
Removed unused ObjectToString method from MySQLParameter.cs
Fixed Add(..) method in ParameterCollection so that it doesn't use Add(name, value) instead.
Fixed IndexOf and Contains in ParameterCollection to be aware that parameter names are now stored without @
Fixed Command.ConvertSQLToBytes so it only allows characters that can be in MySQL variable names
Fixed DataReader and Field so that blob fields read their data from Field.cs and GetBytes works right
Added simple query builder editor to CommandText property of MySQLCommand
Fixed CommandBuilder and Parameter serialization to account for Parameters not storing @ in their names
Removed MySQLFieldType enum from Field.cs. Now using MySQLDbType enum
Added Designer attribute to several classes to prevent designer view when using VS.Net
Fixed Initial catalog typo in ConnectionString designer
Removed 3 parameter ctor for MySQLParameter that conflicted with (name, type, value)
changed MySQLParameter so paramName is now stored without leading @ (this fixed null inserts when using designer)
Changed TypeConverter for MySQLParameter to use the ctor with all properties
Fixed sequence issue in driver
Added DbParametersEditor to make parameter editing more like SqlClient
Fixed Command class so that parameters can be edited using the designer
Update connection string designer to support Use Compression flag
Fixed string encoding so that European characters like ä will work correctly
Creating base classes to aid in building new data providers
Added support for UID key in connection string
Field, parameter, command now using DBNull.Value instead of null
CommandBuilder using DBNull.Value
CommandBuilder now builds insert command correctly when an auto_insert field is not present
Field now uses typeof keyword to return System.Types (performance)
MySQLCommandBuilder now implemented
Transaction support now implemented (not all table types support this)
GetSchemaTable fixed to not use xsd (for Mono)
Driver is now Mono-compatible!!
TIME data type now supported
More work to improve Timestamp data type handling
Changed signatures of all classes to match corresponding SqlClient classes
Protocol compression using SharpZipLib (www.icsharpcode.net)
Named pipes on Windows now working properly
Work done to improve Timestamp data type handling
Implemented IEnumerable on DataReader so DataGrid would work
MySQL provides connectivity for client applications developed in the Java programming language via a JDBC driver, which is called MySQL Connector/J.
MySQL Connector/J is a JDBC-3.0 “Type 4” driver, which means that is pure Java, implements version 3.0 of the JDBC specification, and communicates directly with the MySQL server using the MySQL protocol.
This document is arranged for a beginning JDBC developer. If you are already experienced with using JDBC, you might consider starting with the section Section 26.3.2, “Installing Connector/J”.
Although JDBC is useful by itself, we would hope that if you are not familiar with JDBC that after reading the first few sections of this manual, that you would avoid using “naked” JDBC for all but the most trivial problems and consider using one of the popular persistence frameworks such as Hibernate, Spring's JDBC templates or Ibatis SQL Maps to do the majority of repetitive work and heavier lifting that is sometimes required with JDBC.
This section is not designed to be a complete JDBC tutorial. If you need more information about using JDBC you might be interested in the following online tutorials that are more in-depth than the information presented here:
JDBC Basics — A tutorial from Sun covering beginner topics in JDBC
JDBC Short Course — A more in-depth tutorial from Sun and JGuru
This section provides some general JDBC background.
When you are using JDBC outside of an application server, the
DriverManager
class manages the establishment
of Connections.
The DriverManager
needs to be told which JDBC
drivers it should try to make Connections with. The easiest way
to do this is to use Class.forName()
on the
class that implements the java.sql.Driver
interface. With MySQL Connector/J, the name of this class is
com.mysql.jdbc.Driver
. With this method, you
could use an external configuration file to supply the driver
class name and driver parameters to use when connecting to a
database.
The following section of Java code shows how you might register
MySQL Connector/J from the main()
method of
your application:
import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; // Notice, do not import com.mysql.jdbc.* // or you will have problems! public class LoadDriver { public static void main(String[] args) { try { // The newInstance() call is a work around for some // broken Java implementations Class.forName("com.mysql.jdbc.Driver").newInstance(); } catch (Exception ex) { // handle the error } }
After the driver has been registered with the
DriverManager
, you can obtain a
Connection
instance that is connected to a
particular database by calling
DriverManager.getConnection()
:
Example 26.1. Obtaining a Connection From the DriverManager
This example shows how you can obtain a
Connection
instance from the
DriverManager
. There are a few different
signatures for the getConnection()
method. You should see the API documentation that comes with
your JDK for more specific information on how to use them.
import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; ... try { Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/test?user=monty&password=greatsqldb"); // Do something with the Connection .... } catch (SQLException ex) { // handle any errors System.out.println("SQLException: " + ex.getMessage()); System.out.println("SQLState: " + ex.getSQLState()); System.out.println("VendorError: " + ex.getErrorCode()); }
Once a Connection
is established, it
can be used to create Statement
and
PreparedStatement
objects, as well as
retrieve metadata about the database. This is explained in the
following sections.
Statement
objects allow you to execute
basic SQL queries and retrieve the results through the
ResultSet
class which is described later.
To create a Statement
instance, you call
the createStatement()
method on the
Connection
object you have retrieved via one
of the DriverManager.getConnection()
or
DataSource.getConnection()
methods
described earlier.
Once you have a Statement
instance, you
can execute a SELECT
query by calling the
executeQuery(String)
method with the SQL you
want to use.
To update data in the database, use the
executeUpdate(String SQL)
method. This method
returns the number of rows affected by the update statement.
If you don't know ahead of time whether the SQL statement will
be a SELECT
or an
UPDATE
/INSERT
, then you
can use the execute(String SQL)
method. This
method will return true if the SQL query was a
SELECT
, or false if it was an
UPDATE
, INSERT
, or
DELETE
statement. If the statement was a
SELECT
query, you can retrieve the results by
calling the getResultSet()
method. If the
statement was an UPDATE
,
INSERT
, or DELETE
statement, you can retrieve the affected rows count by calling
getUpdateCount()
on the
Statement
instance.
Example 26.2. Using java.sql.Statement to Execute a SELECT Query
// assume that conn is an already created JDBC connection Statement stmt = null; ResultSet rs = null; try { stmt = conn.createStatement(); rs = stmt.executeQuery("SELECT foo FROM bar"); // or alternatively, if you don't know ahead of time that // the query will be a SELECT... if (stmt.execute("SELECT foo FROM bar")) { rs = stmt.getResultSet(); } // Now do something with the ResultSet .... } finally { // it is a good idea to release // resources in a finally{} block // in reverse-order of their creation // if they are no-longer needed if (rs != null) { try { rs.close(); } catch (SQLException sqlEx) { // ignore } rs = null; } if (stmt != null) { try { stmt.close(); } catch (SQLException sqlEx) { // ignore } stmt = null; } }
Starting with MySQL server version 5.0 when used with
Connector/J 3.1.1 or newer, the
java.sql.CallableStatement
interface is
fully implemented with the exception of the
getParameterMetaData()
method.
MySQL's stored procedure syntax is documented in the "Stored Procedures and Functions" section of the MySQL Reference Manual.
Connector/J exposes stored procedure functionality through
JDBC's CallableStatement
interface.
The following example shows a stored procedure that returns the
value of inOutParam
incremented by 1, and the
string passed in via inputParam
as a
ResultSet
:
Example 26.3. Stored Procedure Example
CREATE PROCEDURE demoSp(IN inputParam VARCHAR(255), INOUT inOutParam INT) BEGIN DECLARE z INT; SET z = inOutParam + 1; SET inOutParam = z; SELECT inputParam; SELECT CONCAT('zyxw', inputParam); END
To use the demoSp
procedure with
Connector/J, follow these steps:
Prepare the callable statement by using
Connection.prepareCall()
.
Notice that you have to use JDBC escape syntax, and that the parentheses surrounding the parameter placeholders are not optional:
Example 26.4. Using Connection.prepareCall()
import java.sql.CallableStatement; ... // // Prepare a call to the stored procedure 'demoSp' // with two parameters // // Notice the use of JDBC-escape syntax ({call ...}) // CallableStatement cStmt = conn.prepareCall("{call demoSp(?, ?)}"); cStmt.setString(1, "abcdefg");
Connection.prepareCall()
is an
expensive method, due to the metadata retrieval that the
driver performs to support output parameters. For
performance reasons, you should try to minimize
unnecessary calls to
Connection.prepareCall()
by reusing
CallableStatement
instances in your
code.
Register the output parameters (if any exist)
To retrieve the values of output parameters (parameters
specified as OUT
or
INOUT
when you created the stored
procedure), JDBC requires that they be specified before
statement execution using the various
registerOutputParameter()
methods in
the CallableStatement
interface:
Example 26.5. Registering Output Parameters
import java.sql.Types; ... // // Connector/J supports both named and indexed // output parameters. You can register output // parameters using either method, as well // as retrieve output parameters using either // method, regardless of what method was // used to register them. // // The following examples show how to use // the various methods of registering // output parameters (you should of course // use only one registration per parameter). // // // Registers the second parameter as output, and // uses the type 'INTEGER' for values returned from // getObject() // cStmt.registerOutParameter(2, Types.INTEGER); // // Registers the named parameter 'inOutParam', and // uses the type 'INTEGER' for values returned from // getObject() // cStmt.registerOutParameter("inOutParam", Types.INTEGER); ...
Set the input parameters (if any exist)
Input and in/out parameters are set as for
PreparedStatement
objects. However,
CallableStatement
also supports
setting parameters by name:
Example 26.6. Setting CallableStatement
Input Parameters
... // // Set a parameter by index // cStmt.setString(1, "abcdefg"); // // Alternatively, set a parameter using // the parameter name // cStmt.setString("inputParameter", "abcdefg"); // // Set the 'in/out' parameter using an index // cStmt.setInt(2, 1); // // Alternatively, set the 'in/out' parameter // by name // cStmt.setInt("inOutParam", 1); ...
Execute the CallableStatement
, and
retrieve any result sets or output parameters.
Although CallableStatement
supports
calling any of the Statement
execute
methods (executeUpdate()
,
executeQuery()
or
execute()
), the most flexible method to
call is execute()
, as you do not need
to know ahead of time if the stored procedure returns result
sets:
Example 26.7. Retrieving Results and Output Parameter Values
... boolean hadResults = cStmt.execute(); // // Process all returned result sets // while (hadResults) { ResultSet rs = cStmt.getResultSet(); // process result set ... hadResults = cStmt.getMoreResults(); } // // Retrieve output parameters // // Connector/J supports both index-based and // name-based retrieval // int outputValue = cStmt.getInt(2); // index-based outputValue = cStmt.getInt("inOutParam"); // name-based ...
Before version 3.0 of the JDBC API, there was no standard way of
retrieving key values from databases that supported “auto
increment” or identity columns. With older JDBC drivers
for MySQL, you could always use a MySQL-specific method on the
Statement
interface, or issue the query
SELECT LAST_INSERT_ID()
after issuing an
INSERT
to a table that had an
AUTO_INCREMENT
key. Using the MySQL-specific
method call isn't portable, and issuing a
SELECT
to get the
AUTO_INCREMENT
key's value requires another
round-trip to the database, which isn't as efficient as
possible. The following code snippets demonstrate the three
different ways to retrieve AUTO_INCREMENT
values. First, we demonstrate the use of the new JDBC-3.0 method
getGeneratedKeys()
which is now the
preferred method to use if you need to retrieve
AUTO_INCREMENT
keys and have access to
JDBC-3.0. The second example shows how you can retrieve the same
value using a standard SELECT
LAST_INSERT_ID()
query. The final example shows how
updatable result sets can retrieve the
AUTO_INCREMENT
value when using the
insertRow()
method.
Example 26.8. Retrieving AUTO_INCREMENT
Column Values using
Statement.getGeneratedKeys()
Statement stmt = null; ResultSet rs = null; try { // // Create a Statement instance that we can use for // 'normal' result sets assuming you have a // Connection 'conn' to a MySQL database already // available stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_UPDATABLE); // // Issue the DDL queries for the table for this example // stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial"); stmt.executeUpdate( "CREATE TABLE autoIncTutorial (" + "priKey INT NOT NULL AUTO_INCREMENT, " + "dataField VARCHAR(64), PRIMARY KEY (priKey))"); // // Insert one row that will generate an AUTO INCREMENT // key in the 'priKey' field // stmt.executeUpdate( "INSERT INTO autoIncTutorial (dataField) " + "values ('Can I Get the Auto Increment Field?')", Statement.RETURN_GENERATED_KEYS); // // Example of using Statement.getGeneratedKeys() // to retrieve the value of an auto-increment // value // int autoIncKeyFromApi = -1; rs = stmt.getGeneratedKeys(); if (rs.next()) { autoIncKeyFromApi = rs.getInt(1); } else { // throw an exception from here } rs.close(); rs = null; System.out.println("Key returned from getGeneratedKeys():" + autoIncKeyFromApi); } finally { if (rs != null) { try { rs.close(); } catch (SQLException ex) { // ignore } } if (stmt != null) { try { stmt.close(); } catch (SQLException ex) { // ignore } } }
Example 26.9. Retrieving AUTO_INCREMENT
Column Values using
SELECT LAST_INSERT_ID()
Statement stmt = null; ResultSet rs = null; try { // // Create a Statement instance that we can use for // 'normal' result sets. stmt = conn.createStatement(); // // Issue the DDL queries for the table for this example // stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial"); stmt.executeUpdate( "CREATE TABLE autoIncTutorial (" + "priKey INT NOT NULL AUTO_INCREMENT, " + "dataField VARCHAR(64), PRIMARY KEY (priKey))"); // // Insert one row that will generate an AUTO INCREMENT // key in the 'priKey' field // stmt.executeUpdate( "INSERT INTO autoIncTutorial (dataField) " + "values ('Can I Get the Auto Increment Field?')"); // // Use the MySQL LAST_INSERT_ID() // function to do the same thing as getGeneratedKeys() // int autoIncKeyFromFunc = -1; rs = stmt.executeQuery("SELECT LAST_INSERT_ID()"); if (rs.next()) { autoIncKeyFromFunc = rs.getInt(1); } else { // throw an exception from here } rs.close(); System.out.println("Key returned from " + "'SELECT LAST_INSERT_ID()': " + autoIncKeyFromFunc); } finally { if (rs != null) { try { rs.close(); } catch (SQLException ex) { // ignore } } if (stmt != null) { try { stmt.close(); } catch (SQLException ex) { // ignore } } }
Example 26.10. Retrieving AUTO_INCREMENT
Column Values in
Updatable ResultSets
Statement stmt = null; ResultSet rs = null; try { // // Create a Statement instance that we can use for // 'normal' result sets as well as an 'updatable' // one, assuming you have a Connection 'conn' to // a MySQL database already available // stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_UPDATABLE); // // Issue the DDL queries for the table for this example // stmt.executeUpdate("DROP TABLE IF EXISTS autoIncTutorial"); stmt.executeUpdate( "CREATE TABLE autoIncTutorial (" + "priKey INT NOT NULL AUTO_INCREMENT, " + "dataField VARCHAR(64), PRIMARY KEY (priKey))"); // // Example of retrieving an AUTO INCREMENT key // from an updatable result set // rs = stmt.executeQuery("SELECT priKey, dataField " + "FROM autoIncTutorial"); rs.moveToInsertRow(); rs.updateString("dataField", "AUTO INCREMENT here?"); rs.insertRow(); // // the driver adds rows at the end // rs.last(); // // We should now be on the row we just inserted // int autoIncKeyFromRS = rs.getInt("priKey"); rs.close(); rs = null; System.out.println("Key returned for inserted row: " + autoIncKeyFromRS); } finally { if (rs != null) { try { rs.close(); } catch (SQLException ex) { // ignore } } if (stmt != null) { try { stmt.close(); } catch (SQLException ex) { // ignore } } }
When you run the preceding example code, you should get the
following output: Key returned from
getGeneratedKeys()
: 1 Key returned from
SELECT LAST_INSERT_ID()
: 1 Key returned for
inserted row: 2 You should be aware, that at times, it can be
tricky to use the SELECT LAST_INSERT_ID()
query, as that function's value is scoped to a connection. So,
if some other query happens on the same connection, the value
will be overwritten. On the other hand, the
getGeneratedKeys()
method is scoped by the
Statement
instance, so it can be used
even if other queries happen on the same connection, but not on
the same Statement
instance.
Use the following instructions to install Connector/J
MySQL Connector/J supports Java-2 JVMs, including JDK-1.2.x, JDK-1.3.x, JDK-1.4.x and JDK-1.5.x, and requires JDK-1.4.x or newer to compile (but not run). MySQL Connector/J does not support JDK-1.1.x or JDK-1.0.x
Because of the implementation of
java.sql.Savepoint
, Connector/J 3.1.0
and newer will not run on JDKs older than 1.4 unless the class
verifier is turned off (-Xverify:none
), as
the class verifier will try to load the class definition for
java.sql.Savepoint
even though it is
not accessed by the driver unless you actually use savepoint
functionality.
Caching functionality provided by Connector/J 3.1.0 or newer
is also not available on JVMs older than 1.4.x, as it relies
on java.util.LinkedHashMap
which was
first available in JDK-1.4.0.
MySQL Connector/J supports all known MySQL server versions. Some features (foreign keys, updatable result sets) require more recent versions of MySQL to operate.
When connecting to MySQL server version 4.1 or newer, it is best to use MySQL Connector/J version 3.1, as it has full support for features in the newer versions of the server, including Unicode characters, views, stored procedures and server-side prepared statements.
Although Connector/J version 3.0 will connect to MySQL server, version 4.1 or newer, and implements Unicode characters and the new authorization mechanism, Connector/J 3.0 will not be updated to support new features in current and future server versions.
MySQL Connector/J is distributed as a .zip or .tar.gz archive
containing the sources, the class files a class-file only
“binary” .jar archive named
"mysql-connector-java-[version]-bin.jar
",
and starting with Connector/J 3.1.8 a “debug”
build of the driver in a file named
"mysql-connector-java-[version]-bin-g.jar
".
Starting with Connector/J 3.1.9, we don't ship the .class files “unbundled,” they are only available in the JAR archives that ship with the driver.
You should not use the “debug” build of the
driver unless instructed to do so when reporting a problem or
bug to MySQL AB, as it is not designed to be run in production
environments, and will have adverse performance impact when
used. The debug binary also depends on the Aspect/J runtime
library, which is located in the
src/lib/aspectjrt.jar
file that comes
with the Connector/J distribution.
You will need to use the appropriate graphical or command-line utility to un-archive the distribution (for example, WinZip for the .zip archive, and tar for the .tar.gz archive). Because there are potentially long filenames in the distribution, we use the GNU tar archive format. You will need to use GNU tar (or an application that understands the GNU tar archive format) to unpack the .tar.gz variant of the distribution.
Once you have extracted the distribution archive, you can install the driver by placing mysql-connector-java-[version]-bin.jar in your classpath, either by adding the FULL path to it to your CLASSPATH environment variable, or by directly specifying it with the command line switch -cp when starting your JVM
If you are going to use the driver with the JDBC DriverManager, you would use "com.mysql.jdbc.Driver" as the class that implements java.sql.Driver.
Example 26.11. Setting the CLASSPATH Under UNIX
The following command works for 'csh' under UNIX:
$ setenv CLASSPATH /path/to/mysql-connector-java-[version]-bin.jar:$CLASSPATH
The above command can be added to the appropriate startup file for the login shell to make MySQL Connector/J available to all Java applications.
If you want to use MySQL Connector/J with an application server such as Tomcat or JBoss, you will have to read your vendor's documentation for more information on how to configure third-party class libraries, as most application servers ignore the CLASSPATH environment variable. This document does contain configuration examples for some J2EE application servers in the section named "Using Connector/J with J2EE and Other Java Frameworks", however the authoritative source for JDBC connection pool configuration information for your particular application server is the documentation for that application server.
If you are developing servlets or JSPs, and your application server is J2EE-compliant, you can put the driver's .jar file in the WEB-INF/lib subdirectory of your webapp, as this is a standard location for third party class libraries in J2EE web applications.
You can also use the MysqlDataSource or MysqlConnectionPoolDataSource classes in the com.mysql.jdbc.jdbc2.optional package, if your J2EE application server supports or requires them. Starting with Connector/J 5.0.0, the javax.sql.XADataSource interface is implemented via the com.mysql.jdbc.jdbc2.optional.MysqlXADataSource class, which supports XA distributed transactions when used in combination with MySQL server version 5.0.
The various MysqlDataSource classes support the following parameters (through standard "set" mutators):
user
password
serverName (see the previous section about fail-over hosts)
databaseName
port
MySQL AB tries to keep the upgrade process as easy as possible, however as is the case with any software, sometimes changes need to be made in new versions to support new features, improve existing functionality, or comply with new standards.
This section has information about what users who are upgrading from one version of Connector/J to another (or to a new version of the MySQL server, with respect to JDBC functionality) should be aware of.
Connector/J 3.1 is designed to be backward-compatible with Connector/J 3.0 as much as possible. Major changes are isolated to new functionality exposed in MySQL-4.1 and newer, which includes Unicode character sets, server-side prepared statements, SQLState codes returned in error messages by the server and various performance enhancements that can be enabled or disabled via configuration properties.
Unicode Character Sets - See the next section, as well as the "Character Sets" section in the server manual for information on this new feature of MySQL. If you have something misconfigured, it will usually show up as an error with a message similar to 'Illegal mix of collations'.
Server-side Prepared Statements - Connector/J 3.1 will automatically detect and use server-side prepared statements when they are available (MySQL server version 4.1.0 and newer).
Starting with version 3.1.7, the driver scans SQL you are
preparing via all variants of
Connection.prepareStatement()
to
determine if it is a supported type of statement to
prepare on the server side, and if it is not supported by
the server, it instead prepares it as a client-side
emulated prepared statement. You can disable this feature
by passing
'emulateUnsupportedPstmts=false' in
your JDBC URL.
If your application encounters issues with server-side prepared statements, you can revert to the older client-side emulated prepared statement code that is still presently used for MySQL servers older than 4.1.0 with the following connection property:
useServerPrepStmts=false
Datetimes with all-zero components ('0000-00-00 ...') - These values can not be represented reliably in Java. Connector/J 3.0.x always converted them to NULL when being read from a ResultSet.
Connector/J 3.1 throws an exception by default when these values are encountered as this is the most correct behavior according to the JDBC and SQL standards. This behavior can be modified using the ' zeroDateTimeBehavior ' configuration property. The allowable values are: 'exception' (the default), which throws an SQLException with an SQLState of 'S1009', 'convertToNull', which returns NULL instead of the date, and 'round', which rounds the date to the nearest closest value which is '0001-01-01'.
Starting with Connector/J 3.1.7, ResultSet.getString() can be decoupled from this behavior via ' noDatetimeStringSync=true ' (the default value is 'false') so that you can get retrieve the unaltered all-zero value as a String. It should be noted that this also precludes using any timezone conversions, therefore the driver will not allow you to enable noDatetimeStringSync and useTimezone at the same time.
New SQLState Codes - Connector/J 3.1 uses SQL:1999 SQLState codes returned by the MySQL server (if supported), which are different than the “legacy” X/Open state codes that Connector/J 3.0 uses. If connected to a MySQL server older than MySQL-4.1.0 (the oldest version to return SQLStates as part of the error code), the driver will use a built-in mapping. You can revert to the old mapping by using the following configuration property:
useSqlStateCodes=false
Calling ResultSet.getString() on a BLOB column will now return the address of the byte[] array that represents it, instead of a String representation of the BLOB. BLOBs have no character set, so they can't be converted to java.lang.Strings without data loss or corruption.
To store strings in MySQL with LOB behavior, use one of the TEXT types, which the driver will treat as a java.sql.Clob.
Starting with Connector/J 3.1.8 a “debug”
build of the driver in a file named
"mysql-connector-java-[version]-bin-g.jar
"
is shipped alongside the normal “binary” jar
file that is named
"mysql-connector-java-[version]-bin.jar
".
Starting with Connector/J 3.1.9, we don't ship the .class files “unbundled,” they are only available in the JAR archives that ship with the driver.
You should not use the “debug” build of the
driver unless instructed to do so when reporting a problem
or bug to MySQL AB, as it is not designed to be run in
production environments, and will have adverse performance
impact when used. The debug binary also depends on the
Aspect/J runtime library, which is located in the
src/lib/aspectjrt.jar
file that comes
with the Connector/J distribution.
Using the UTF-8 Character Encoding - Prior to MySQL server version 4.1, the UTF-8 character encoding was not supported by the server, however the JDBC driver could use it, allowing storage of multiple character sets in latin1 tables on the server.
Starting with MySQL-4.1, this functionality is deprecated. If you have applications that rely on this functionality, and can not upgrade them to use the official Unicode character support in MySQL server version 4.1 or newer, you should add the following property to your connection URL:
useOldUTF8Behavior=true
Server-side Prepared Statements - Connector/J 3.1 will automatically detect and use server-side prepared statements when they are available (MySQL server version 4.1.0 and newer). If your application encounters issues with server-side prepared statements, you can revert to the older client-side emulated prepared statement code that is still presently used for MySQL servers older than 4.1.0 with the following connection property:
useServerPrepStmts=false
You should read this section only if you are interested in helping us test our new code. If you just want to get MySQL Connector/J up and running on your system, you should use a standard release distribution.
To install MySQL Connector/J from the development source tree, make sure that you have the following prerequisites:
Subversion, to check out the sources from our repository (available from http://subversion.tigris.org/).
Apache Ant version 1.6 or newer (available from http://ant.apache.org/).
JDK-1.4.2 or later. Although MySQL Connector/J can be installed on older JDKs, to compile it from source you must have at least JDK-1.4.2.
The Subversion source code repository for MySQL Connector/J is located at http://svn.mysql.com/svnpublic/connector-j. In general, you should not check out the entire repository because it contains every branch and tag for MySQL Connector/J and is quite large.
To check out and compile a specific branch of MySQL Connector/J, follow these steps:
At the time of this writing, there are three active branches
of Connector/J: branch_3_0
,
branch_3_1
and
branch_5_0
. Check out the latest code
from the branch that you want with the following command
(replacing [major]
and
[minor]
with appropriate version
numbers):
shell> svn co http://svn.mysql.com/svnpublic/connector-j/branches/branch_[major]
_[minor]
/connector-j
This creates a connector-j
subdirectory
in the current directory that contains the latest sources
for the requested branch.
Change location to the connector-j
directory to make it your current working directory:
shell> cd connector-j
Issue the following command to compile the driver and create
a .jar
file suitable for installation:
shell> ant dist
This creates a build
directory in the
current directory, where all build output will go. A
directory is created in the build
directory that includes the version number of the sources
you are building from. This directory contains the sources,
compiled .class
files, and a
.jar
file suitable for deployment. For
other possible targets, including ones that will create a
fully packaged distribution, issue the following command:
shell> ant --projecthelp
A newly created .jar
file containing
the JDBC driver will be placed in the directory
build/mysql-connector-java-
.
[version]
Install the newly created JDBC driver as you would a binary
.jar
file that you download from MySQL
by following the instructions in
Section 26.3.2.1.3, “Installing the Driver and Configuring the CLASSPATH
”.
The name of the class that implements java.sql.Driver in MySQL Connector/J is 'com.mysql.jdbc.Driver'. The 'org.gjt.mm.mysql.Driver' class name is also usable to remain backward-compatible with MM.MySQL. You should use this class name when registering the driver, or when otherwise configuring software to use MySQL Connector/J.
The JDBC URL format for MySQL Connector/J is as follows, with items in square brackets ([, ]) being optional:
jdbc:mysql://[host][,failoverhost...][:port]/[database][?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...
If the hostname is not specified, it defaults to '127.0.0.1'. If the port is not specified, it defaults to '3306', the default port number for MySQL servers.
jdbc:mysql://[host:port],[host:port].../[database][?propertyName1][=propertyValue1][&propertyName2][=propertyValue2]...
If the database is not specified, the connection will be made
with no default database. In this case, you will need to either
call the setCatalog()
method on the
Connection instance or fully-specify table names using the
database name (i.e. 'SELECT dbname.tablename.colname FROM
dbname.tablename...') in your SQL. Not specifying the database
to use upon connection is generally only useful when building
tools that work with multiple databases, such as GUI database
managers.
MySQL Connector/J has fail-over support. This allows the driver to fail-over to any number of “slave” hosts and still perform read-only queries. Fail-over only happens when the connection is in an autoCommit(true) state, because fail-over can not happen reliably when a transaction is in progress. Most application servers and connection pools set autoCommit to 'true' at the end of every transaction/connection use.
The fail-over functionality has the following behavior:
If the URL property "autoReconnect" is false: Failover only happens at connection initialization, and failback occurs when the driver determines that the first host has become available again.
If the URL property "autoReconnect" is true: Failover happens when the driver determines that the connection has failed (before every query), and falls back to the first host when it determines that the host has become available again (after queriesBeforeRetryMaster queries have been issued).
In either case, whenever you are connected to a "failed-over" server, the connection will be set to read-only state, so queries that would modify data will have exceptions thrown (the query will never be processed by the MySQL server).
Configuration properties define how Connector/J will make a connection to a MySQL server. Unless otherwise noted, properties can be set for a DataSource object or for a Connection object.
Configuration Properties can be set in one of the following ways:
Using the set*() methods on MySQL implementations of java.sql.DataSource (which is the preferred method when using implementations of java.sql.DataSource):
com.mysql.jdbc.jdbc2.optional.MysqlDataSource
com.mysql.jdbc.jdbc2.optional.MysqlConnectionPoolDataSource
As a key/value pair in the java.util.Properties instance passed to DriverManager.getConnection() or Driver.connect()
As a JDBC URL parameter in the URL given to java.sql.DriverManager.getConnection(), java.sql.Driver.connect() or the MySQL implementations of javax.sql.DataSource's setURL() method.
If the mechanism you use to configure a JDBC URL is XML-based, you will need to use the XML character literal & to separate configuration parameters, as the ampersand is a reserved character for XML.
The properties are listed in the following table:
Table 26.1. Connection Properties
Property Name | Definition | Required? | Default Value | Since Version |
---|---|---|---|---|
Connection/Authentication | ||||
user | The user to connect as | No | all | |
password | The password to use when connecting | No | all | |
socketFactory | The name of the class that the driver should use for creating socket connections to the server. This class must implement the interface 'com.mysql.jdbc.SocketFactory' and have public no-args constructor. | No | com.mysql.jdbc.StandardSocketFactory | 3.0.3 |
connectTimeout | Timeout for socket connect (in milliseconds), with 0 being no timeout. Only works on JDK-1.4 or newer. Defaults to '0'. | No | 0 | 3.0.1 |
socketTimeout | Timeout on network socket operations (0, the default means no timeout). | No | 0 | 3.0.1 |
useConfigs | Load the comma-delimited list of configuration properties before parsing the URL or applying user-specified properties. These configurations are explained in the 'Configurations' of the documentation. | No | 3.1.5 | |
interactiveClient | Set the CLIENT_INTERACTIVE flag, which tells MySQL to timeout connections based on INTERACTIVE_TIMEOUT instead of WAIT_TIMEOUT | No | false | 3.1.0 |
propertiesTransform | An implementation of com.mysql.jdbc.ConnectionPropertiesTransform that the driver will use to modify URL properties passed to the driver before attempting a connection | No | 3.1.4 | |
useCompression | Use zlib compression when communicating with the server (true/false)? Defaults to 'false'. | No | false | 3.0.17 |
High Availability and Clustering | ||||
autoReconnect | Should the driver try to re-establish stale or dead connections? If enabled the driver will throw an exception for a queries issued on a stale or dead connection, which belong to the current transaction, but will attempt reconnect before the next query issued on the connection in a new transaction. The use of this feature is not recommended, because it has side effects related to session state and data consistency when applications don'thandle SQLExceptions properly, and is only designed to be used when you are unable to configure your application to handle SQLExceptions resulting from dead andstale connections properly. Alternatively, investigate setting the MySQL server variable "wait_timeout"to some high value rather than the default of 8 hours. | No | false | 1.1 |
autoReconnectForPools | Use a reconnection strategy appropriate for connection pools (defaults to 'false') | No | false | 3.1.3 |
failOverReadOnly | When failing over in autoReconnect mode, should the connection be set to 'read-only'? | No | true | 3.0.12 |
reconnectAtTxEnd | If autoReconnect is set to true, should the driver attempt reconnectionsat the end of every transaction? | No | false | 3.0.10 |
roundRobinLoadBalance | When autoReconnect is enabled, and failoverReadonly is false, should we pick hosts to connect to on a round-robin basis? | No | false | 3.1.2 |
queriesBeforeRetryMaster | Number of queries to issue before falling back to master when failed over (when using multi-host failover). Whichever condition is met first, 'queriesBeforeRetryMaster' or 'secondsBeforeRetryMaster' will cause an attempt to be made to reconnect to the master. Defaults to 50. | No | 50 | 3.0.2 |
secondsBeforeRetryMaster | How long should the driver wait, when failed over, before attempting to reconnect to the master server? Whichever condition is met first, 'queriesBeforeRetryMaster' or 'secondsBeforeRetryMaster' will cause an attempt to be made to reconnect to the master. Time in seconds, defaults to 30 | No | 30 | 3.0.2 |
enableDeprecatedAutoreconnect | Auto-reconnect functionality is deprecated starting with version 3.2, and will be removed in version 3.3. Set this property to 'true' to disable the check for the feature being configured. | No | false | 3.2.1 |
Security | ||||
allowMultiQueries | Allow the use of ';' to delimit multiple queries during one statement (true/false, defaults to 'false' | No | false | 3.1.1 |
useSSL | Use SSL when communicating with the server (true/false), defaults to 'false' | No | false | 3.0.2 |
requireSSL | Require SSL connection if useSSL=true? (defaults to 'false'). | No | false | 3.1.0 |
allowUrlInLocalInfile | Should the driver allow URLs in 'LOAD DATA LOCAL INFILE' statements? | No | false | 3.1.4 |
paranoid | Take measures to prevent exposure sensitive information in error messages and clear data structures holding sensitive data when possible? (defaults to 'false') | No | false | 3.0.1 |
Performance Extensions | ||||
metadataCacheSize | The number of queries to cacheResultSetMetadata for if cacheResultSetMetaData is set to 'true' (default 50) | No | 50 | 3.1.1 |
prepStmtCacheSize | If prepared statement caching is enabled, how many prepared statements should be cached? | No | 25 | 3.0.10 |
prepStmtCacheSqlLimit | If prepared statement caching is enabled, what's the largest SQL the driver will cache the parsing for? | No | 256 | 3.0.10 |
useCursorFetch | If connected to MySQL > 5.0.2, and setFetchSize() > 0 on a statement, should that statement use cursor-based fetching to retrieve rows? | No | false | 5.0.0 |
blobSendChunkSize | Chunk to use when sending BLOB/CLOBs via ServerPreparedStatements | No | 1048576 | 3.1.9 |
cacheCallableStmts | Should the driver cache the parsing stage of CallableStatements | No | false | 3.1.2 |
cachePrepStmts | Should the driver cache the parsing stage of PreparedStatements of client-side prepared statements, the “check” for suitability of server-side prepared and server-side prepared statements themselves? | No | false | 3.0.10 |
cacheResultSetMetadata | Should the driver cache ResultSetMetaData for Statements and PreparedStatements? (Req. JDK-1.4+, true/false, default 'false') | No | false | 3.1.1 |
cacheServerConfiguration | Should the driver cache the results of 'SHOW VARIABLES' and 'SHOW COLLATION' on a per-URL basis? | No | false | 3.1.5 |
defaultFetchSize | The driver will call setFetchSize(n) with this value on all newly-created Statements | No | 0 | 3.1.9 |
dontTrackOpenResources | The JDBC specification requires the driver to automatically track and close resources, however if your application doesn't do a good job of explicitly calling close() on statements or result sets, this can cause memory leakage. Setting this property to true relaxes this constraint, and can be more memory efficient for some applications. | No | false | 3.1.7 |
dynamicCalendars | Should the driver retrieve the default calendar when required, or cache it per connection/session? | No | false | 3.1.5 |
elideSetAutoCommits | If using MySQL-4.1 or newer, should the driver only issue 'set autocommit=n' queries when the server's state doesn't match the requested state by Connection.setAutoCommit(boolean)? | No | false | 3.1.3 |
holdResultsOpenOverStatementClose | Should the driver close result sets on Statement.close() as required by the JDBC specification? | No | false | 3.1.7 |
locatorFetchBufferSize | If 'emulateLocators' is configured to 'true', what size buffer should be used when fetching BLOB data for getBinaryInputStream? | No | 1048576 | 3.2.1 |
useFastIntParsing | Use internal String->Integer conversion routines to avoid excessive object creation? | No | true | 3.1.4 |
useLocalSessionState | Should the driver refer to the internal values of autocommit and transaction isolation that are set by Connection.setAutoCommit() and Connection.setTransactionIsolation(), rather than querying the database? | No | false | 3.1.7 |
useReadAheadInput | Use newer, optimized non-blocking, buffered input stream when reading from the server? | No | true | 3.1.5 |
Debuging/Profiling | ||||
logger | The name of a class that implements 'com.mysql.jdbc.log.Log' that will be used to log messages to.(default is 'com.mysql.jdbc.log.StandardLogger', which logs to STDERR) | No | com.mysql.jdbc.log.StandardLogger | 3.1.1 |
profileSQL | Trace queries and their execution/fetch times to the configured logger (true/false) defaults to 'false' | No | false | 3.1.0 |
reportMetricsIntervalMillis | If 'gatherPerfMetrics' is enabled, how often should they be logged (in ms)? | No | 30000 | 3.1.2 |
maxQuerySizeToLog | Controls the maximum length/size of a query that will get logged when profiling or tracing | No | 2048 | 3.1.3 |
packetDebugBufferSize | The maximum number of packets to retain when 'enablePacketDebug' is true | No | 20 | 3.1.3 |
slowQueryThresholdMillis | If 'logSlowQueries' is enabled, how long should a query (in ms) before it is logged as 'slow'? | No | 2000 | 3.1.2 |
useUsageAdvisor | Should the driver issue 'usage' warnings advising proper and efficient usage of JDBC and MySQL Connector/J to the log (true/false, defaults to 'false')? | No | false | 3.1.1 |
autoGenerateTestcaseScript | Should the driver dump the SQL it is executing, including server-side prepared statements to STDERR? | No | false | 3.1.9 |
dumpMetadataOnColumnNotFound | Should the driver dump the field-level metadata of a result set into the exception message when ResultSet.findColumn() fails? | No | false | 3.1.13 |
dumpQueriesOnException | Should the driver dump the contents of the query sent to the server in the message for SQLExceptions? | No | false | 3.1.3 |
enablePacketDebug | When enabled, a ring-buffer of 'packetDebugBufferSize' packets will be kept, and dumped when exceptions are thrown in key areas in the driver's code | No | false | 3.1.3 |
explainSlowQueries | If 'logSlowQueries' is enabled, should the driver automatically issue an 'EXPLAIN' on the server and send the results to the configured log at a WARN level? | No | false | 3.1.2 |
logSlowQueries | Should queries that take longer than 'slowQueryThresholdMillis' be logged? | No | false | 3.1.2 |
traceProtocol | Should trace-level network protocol be logged? | No | false | 3.1.2 |
Miscellaneous | ||||
useUnicode | Should the driver use Unicode character encodings when handling strings? Should only be used when the driver can't determine the character set mapping, or you are trying to 'force' the driver to use a character set that MySQL either doesn't natively support (such as UTF-8), true/false, defaults to 'true' | No | true | 1.1g |
characterEncoding | If 'useUnicode' is set to true, what character encoding should the driver use when dealing with strings? (defaults is to 'autodetect') | No | 1.1g | |
characterSetResults | Character set to tell the server to return results as. | No | 3.0.13 | |
connectionCollation | If set, tells the server to use this collation via 'set collation_connection' | No | 3.0.13 | |
sessionVariables | A comma-separated list of name/value pairs to be sent as SET SESSION ... to the server when the driver connects. | No | 3.1.8 | |
allowNanAndInf | Should the driver allow NaN or +/- INF values in PreparedStatement.setDouble()? | No | false | 3.1.5 |
autoClosePStmtStreams | Should the driver automatically call .close() on streams/readers passed as arguments via set*() methods? | No | false | 3.1.12 |
autoDeserialize | Should the driver automatically detect and de-serialize objects stored in BLOB fields? | No | false | 3.1.5 |
capitalizeTypeNames | Capitalize type names in DatabaseMetaData? (usually only useful when using WebObjects, true/false, defaults to 'false') | No | false | 2.0.7 |
clobCharacterEncoding | The character encoding to use for sending and retrieving TEXT, MEDIUMTEXT and LONGTEXT values instead of the configured connection characterEncoding | No | 5.0.0 | |
clobberStreamingResults | This will cause a 'streaming' ResultSet to be automatically closed, and any outstanding data still streaming from the server to be discarded if another query is executed before all the data has been read from the server. | No | false | 3.0.9 |
continueBatchOnError | Should the driver continue processing batch commands if one statement fails. The JDBC spec allows either way (defaults to 'true'). | No | true | 3.0.3 |
createDatabaseIfNotExist | Creates the database given in the URL if it doesn't yet exist. Assumes the configured user has permissions to create databases. | No | false | 3.1.9 |
emptyStringsConvertToZero | Should the driver allow conversions from empty string fields to numeric values of '0'? | No | true | 3.1.8 |
emulateLocators | N/A | No | false | 3.1.0 |
emulateUnsupportedPstmts | Should the driver detect prepared statements that are not supported by the server, and replace them with client-side emulated versions? | No | true | 3.1.7 |
ignoreNonTxTables | Ignore non-transactional table warning for rollback? (defaults to 'false'). | No | false | 3.0.9 |
jdbcCompliantTruncation | Should the driver throw java.sql.DataTruncation exceptions when data is truncated as is required by the JDBC specification when connected to a server that supports warnings(MySQL 4.1.0 and newer)? | No | true | 3.1.2 |
maxRows | The maximum number of rows to return (0, the default means return all rows). | No | -1 | all versions |
noDatetimeStringSync | Don't ensure that ResultSet.getDatetimeType().toString().equals(ResultSet.getString()) | No | false | 3.1.7 |
noTimezoneConversionForTimeType | Don't convert TIME values using the server timezone if 'useTimezone'='true' | No | false | 5.0.0 |
nullCatalogMeansCurrent | When DatabaseMetadataMethods ask for a 'catalog' parameter, does the value null mean use the current catalog? (this is not JDBC-compliant, but follows legacy behavior from earlier versions of the driver) | No | true | 3.1.8 |
nullNamePatternMatchesAll | Should DatabaseMetaData methods that accept *pattern parameters treat null the same as '%' (this is not JDBC-compliant, however older versions of the driver accepted this departure from the specification) | No | true | 3.1.8 |
overrideSupportsIntegrityEnhancementFacility | Should the driver return "true" for DatabaseMetaData.supportsIntegrityEnhancementFacility() even if the database doesn't support it to workaround applications that require this method to return "true" to signal support of foreign keys, even though the SQL specification states that this facility contains much more than just foreign key support (one such application being OpenOffice)? | No | false | 3.1.12 |
pedantic | Follow the JDBC spec to the letter. | No | false | 3.0.0 |
processEscapeCodesForPrepStmts | Should the driver process escape codes in queries that are prepared? | No | true | 3.1.12 |
relaxAutoCommit | If the version of MySQL the driver connects to does not support transactions, still allow calls to commit(), rollback() and setAutoCommit() (true/false, defaults to 'false')? | No | false | 2.0.13 |
retainStatementAfterResultSetClose | Should the driver retain the Statement reference in a ResultSet after ResultSet.close() has been called. This is not JDBC-compliant after JDBC-4.0. | No | false | 3.1.11 |
rollbackOnPooledClose | Should the driver issue a rollback() when the logical connection in a pool is closed? | No | true | 3.0.15 |
runningCTS13 | Enables workarounds for bugs in Sun's JDBC compliance testsuite version 1.3 | No | false | 3.1.7 |
serverTimezone | Override detection/mapping of timezone. Used when timezone from server doesn't map to Java timezone | No | 3.0.2 | |
strictFloatingPoint | Used only in older versions of compliance test | No | false | 3.0.0 |
strictUpdates | Should the driver do strict checking (all primary keys selected) of updatable result sets (true, false, defaults to 'true')? | No | true | 3.0.4 |
tinyInt1isBit | Should the driver treat the datatype TINYINT(1) as the BIT type (because the server silently converts BIT -> TINYINT(1) when creating tables)? | No | true | 3.0.16 |
transformedBitIsBoolean | If the driver converts TINYINT(1) to a different type, should it use BOOLEAN instead of BIT for future compatibility with MySQL-5.0, as MySQL-5.0 has a BIT type? | No | false | 3.1.9 |
ultraDevHack | Create PreparedStatements for prepareCall() when required, because UltraDev is broken and issues a prepareCall() for _all_ statements? (true/false, defaults to 'false') | No | false | 2.0.3 |
useGmtMillisForDatetimes | Convert between session timezone and GMT before creating Date and Timestamp instances (value of "false" is legacy behavior, "true" leads to more JDBC-compliant behavior. | No | false | 3.1.12 |
useHostsInPrivileges | Add '@hostname' to users in DatabaseMetaData.getColumn/TablePrivileges() (true/false), defaults to 'true'. | No | true | 3.0.2 |
useInformationSchema | When connected to MySQL-5.0.7 or newer, should the driver use the INFORMATION_SCHEMA to derive information used by DatabaseMetaData? | No | false | 5.0.0 |
useJDBCCompliantTimezoneShift | Should the driver use JDBC-compliant rules when converting TIME/TIMESTAMP/DATETIME values' timezone information for those JDBC arguments which take a java.util.Calendar argument? (Notice that this option is exclusive of the "useTimezone=true" configuration option.) | No | false | 5.0.0 |
useOldUTF8Behavior | Use the UTF-8 behavior the driver did when communicating with 4.0 and older servers | No | false | 3.1.6 |
useOnlyServerErrorMessages | Don't prepend 'standard' SQLState error messages to error messages returned by the server. | No | true | 3.0.15 |
useServerPrepStmts | Use server-side prepared statements if the server supports them? (defaults to 'true'). | No | true | 3.1.0 |
useSqlStateCodes | Use SQL Standard state codes instead of 'legacy' X/Open/SQL state codes (true/false), default is 'true' | No | true | 3.1.3 |
useStreamLengthsInPrepStmts | Honor stream length parameter in PreparedStatement/ResultSet.setXXXStream() method calls (true/false, defaults to 'true')? | No | true | 3.0.2 |
useTimezone | Convert time/date types between client and server timezones (true/false, defaults to 'false')? | No | false | 3.0.2 |
useUnbufferedInput | Don't use BufferedInputStream for reading data from the server | No | true | 3.0.11 |
yearIsDateType | Should the JDBC driver treat the MySQL type "YEAR" as a java.sql.Date, or as a SHORT? | No | true | 3.1.9 |
zeroDateTimeBehavior | What should happen when the driver encounters DATETIME values that are composed entirely of zeroes (used by MySQL to represent invalid dates)? Valid values are 'exception', 'round' and 'convertToNull'. | No | exception | 3.1.4 |
Connector/J also supports access to MySQL via named pipes on Windows NT/2000/XP using the 'NamedPipeSocketFactory' as a plugin-socket factory via the 'socketFactory' property. If you don't use a 'namedPipePath' property, the default of '\\.\pipe\MySQL' will be used. If you use the NamedPipeSocketFactory, the hostname and port number values in the JDBC url will be ignored.
Adding the following property to your URL will enable the NamedPipeSocketFactory:
socketFactory=com.mysql.jdbc.NamedPipeSocketFactory
Named pipes only work when connecting to a MySQL server on the same physical machine as the one the JDBC driver is being used on. In simple performance tests, it appears that named pipe access is between 30%-50% faster than the standard TCP/IP access.
You can create your own socket factories by following the
example code in
com.mysql.jdbc.NamedPipeSocketFactory
, or
com.mysql.jdbc.StandardSocketFactory
.
MySQL Connector/J passes all of the tests in the publicly-available version of Sun's JDBC compliance test suite. However, in many places the JDBC specification is vague about how certain functionality should be implemented, or the specification allows leeway in implementation.
This section gives details on a interface-by-interface level about how certain implementation decisions may affect how you use MySQL Connector/J.
Blob
The Blob implementation does not allow in-place modification (they are 'copies', as reported by the DatabaseMetaData.locatorsUpdateCopies() method). Because of this, you should use the corresponding PreparedStatement.setBlob() or ResultSet.updateBlob() (in the case of updatable result sets) methods to save changes back to the database.
Starting with Connector/J version 3.1.0, you can emulate Blobs with locators by adding the property 'emulateLocators=true' to your JDBC URL. You must then use a column alias with the value of the column set to the actual name of the Blob column in the SELECT that you write to retrieve the Blob. The SELECT must also reference only one table, the table must have a primary key, and the SELECT must cover all columns that make up the primary key. The driver will then delay loading the actual Blob data until you retrieve the Blob and call retrieval methods (getInputStream(), getBytes(), and so forth) on it.
CallableStatement
Starting with Connector/J 3.1.1, stored procedures are
supported when connecting to MySQL version 5.0 or newer via
the CallableStatement
interface.
Currently, the getParameterMetaData()
method of CallableStatement
is not
supported.
Clob
The Clob implementation does not allow in-place modification (they are 'copies', as reported by the DatabaseMetaData.locatorsUpdateCopies() method). Because of this, you should use the PreparedStatement.setClob() method to save changes back to the database. The JDBC API does not have a ResultSet.updateClob() method.
Connection
Unlike older versions of MM.MySQL the
isClosed()
method does not
“ping” the server to determine if it is alive.
In accordance with the JDBC specification, it only returns
true if 'closed()' has been called on the connection. If you
need to determine if the connection is still valid, you
should issue a simple query, such as "SELECT 1". The driver
will throw an exception if the connection is no longer
valid.
DatabaseMetaData
Foreign Key information (getImported/ExportedKeys() and getCrossReference()) is only available from 'InnoDB'-type tables. However, the driver uses 'SHOW CREATE TABLE' to retrieve this information, so when other storage engines support foreign keys, the driver will transparently support them as well.
Driver
PreparedStatement
PreparedStatements are implemented by the driver, as MySQL does not have a prepared statement feature. Because of this, the driver does not implement getParameterMetaData() or getMetaData() as it would require the driver to have a complete SQL parser in the client.
Starting with version 3.1.0 MySQL Connector/J, server-side prepared statements and 'binary-encoded' result sets are used when the server supports them.
Take care when using a server-side prepared statement with “large” parameters that are set via setBinaryStream(), setAsciiStream(), setUnicodeStream(), setBlob(), or setClob(). If you want to re-execute the statement with any “large” parameter changed to a non-“large” parameter, it is necessary to call clearParameters() and set all parameters again. The reason for this is as follows:
The driver streams the 'large' data 'out-of-band' to the prepared statement on the server side when the parameter is set (before execution of the prepared statement).
Once that has been done, the stream used to read the data on the client side is closed (as per the JDBC spec), and can't be read from again.
If a parameter changes from “large” to non-“large,” the driver must reset the server-side state of the prepared statement to allow the parameter that is being changed to take the place of the prior “large” value. This removes all of the 'large' data that has already been sent to the server, thus requiring the data to be re-sent, via the setBinaryStream(), setAsciiStream(), setUnicodeStream(), setBlob() or setClob() methods.
Consequently, if you want to change the “type” of a parameter to a non-“large” one, you must call clearParameters() and set all parameters of the prepared statement again before it can be re-executed.
ResultSet
By default, ResultSets are completely retrieved and stored in memory. In most cases this is the most efficient way to operate, and due to the design of the MySQL network protocol is easier to implement. If you are working with ResultSets that have a large number of rows or large values, and can not allocate heap space in your JVM for the memory required, you can tell the driver to 'stream' the results back one row at a time.
To enable this functionality, you need to create a Statement instance in the following manner:
stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_READ_ONLY); stmt.setFetchSize(Integer.MIN_VALUE);
The combination of a forward-only, read-only result set, with a fetch size of Integer.MIN_VALUE serves as a signal to the driver to “stream” result sets row-by-row. After this any result sets created with the statement will be retrieved row-by-row.
There are some caveats with this approach. You will have to read all of the rows in the result set (or close it) before you can issue any other queries on the connection, or an exception will be thrown.
The earliest the locks these statements hold can be released
(whether they be MyISAM
table-level locks
or row-level locks in some other storage engine such as
InnoDB
) is when the statement completes.
If the statement is within scope of a transaction, then locks are released when the transaction completes (which implies that the statement needs to complete first). As with most other databases, statements are not complete until all the results pending on the statement are read or the active result set for the statement is closed.
Therefore, if using “streaming” results, you should process them as quickly as possible if you want to maintain concurrent access to the tables referenced by the statement producing the result set.
ResultSetMetaData
The "isAutoIncrement()" method only works when using MySQL servers 4.0 and newer.
Statement
When using versions of the JDBC driver earlier than 3.2.1, and connected to server versions earlier than 5.0.3, the "setFetchSize()" method has no effect, other than to toggle result set streaming as described above.
MySQL does not support SQL cursors, and the JDBC driver doesn't emulate them, so "setCursorName()" has no effect.
MySQL Connector/J is flexible in the way it handles conversions between MySQL data types and Java data types.
In general, any MySQL data type can be converted to a java.lang.String, and any numerical type can be converted to any of the Java numerical types, although round-off, overflow, or loss of precision may occur.
Starting with Connector/J 3.1.0, the JDBC driver will issue warnings or throw DataTruncation exceptions as is required by the JDBC specification unless the connection was configured not to do so by using the property "jdbcCompliantTruncation" and setting it to "false".
The conversions that are always guaranteed to work are listed in the following table:
Table 26.2. Conversion Table
These MySQL Data Types | Can always be converted to these Java types |
---|---|
CHAR, VARCHAR, BLOB, TEXT, ENUM, and SET | java.lang.String, java.io.InputStream, java.io.Reader,
java.sql.Blob, java.sql.Clob |
FLOAT, REAL, DOUBLE PRECISION, NUMERIC, DECIMAL, TINYINT, SMALLINT, MEDIUMINT, INTEGER, BIGINT | java.lang.String, java.lang.Short, java.lang.Integer,
java.lang.Long, java.lang.Double,
java.math.BigDecimal
Noteround-off, overflow or loss of precision may occur if you choose a Java numeric data type that has less precision or capacity than the MySQL data type you are converting to/from. |
DATE, TIME, DATETIME, TIMESTAMP | java.lang.String, java.sql.Date,
java.sql.Timestamp |
The ResultSet.getObject()
method uses the
following type conversions between MySQL and Java types,
following the JDBC specification where appropriate:
Table 26.3. MySQL Types to Java Types for ResultSet.getObject()
MySQL Type Name | Returned as Java Class |
---|---|
BIT(1) (new in MySQL-5.0) | java.lang.Boolean |
BIT( > 1) (new in MySQL-5.0) | byte[] |
TINYINT | java.lang.Boolean if the configuration property
"tinyInt1isBit" is set to "true" (the default) and the
storage size is "1", or
java.lang.Integer if not. |
BOOL , BOOLEAN | See TINYINT, above as these are aliases for TINYINT(1), currently. |
SMALLINT[(M)] [UNSIGNED] | java.lang.Integer (regardless if UNSIGNED or not) |
MEDIUMINT[(M)] [UNSIGNED] | java.lang.Integer, if UNSIGNED
java.lang.Long |
INT,INTEGER[(M)] [UNSIGNED] | java.lang.Integer , if UNSIGNED
java.lang.Long |
BIGINT[(M)] [UNSIGNED] | java.lang.Long , if UNSIGNED
java.math.BigInteger |
FLOAT[(M,D)] | java.lang.Float |
DOUBLE[(M,B)] | java.lang.Double |
DECIMAL[(M[,D])] | java.math.BigDecimal |
DATE | java.sql.Date |
DATETIME | java.sql.Timestamp |
TIMESTAMP[(M)] | java.sql.Timestamp |
TIME | java.sql.Time |
YEAR[(2|4)] | java.sql.Date (with the date set two January 1st,
at midnight) |
CHAR(M) | java.lang.String (unless the character set for
the column is BINARY, then
byte[] is returned. |
VARCHAR(M) [BINARY] | java.lang.String (unless the character set for
the column is BINARY, then
byte[] is returned. |
BINARY(M) | byte[] |
VARBINARY(M) | byte[] |
TINYBLOB | byte[] |
TINYTEXT | java.lang.String |
BLOB | byte[] |
TEXT | java.lang.String |
MEDIUMBLOB | byte[] |
MEDIUMTEXT | java.lang.String |
LONGBLOB | byte[] |
LONGTEXT | java.lang.String |
ENUM('value1','value2',...) | java.lang.String |
SET('value1','value2',...) | java.lang.String |
All strings sent from the JDBC driver to the server are
converted automatically from native Java Unicode form to the
client character encoding, including all queries sent via
Statement.execute()
,
Statement.executeUpdate()
,
Statement.executeQuery()
as well as all
PreparedStatement
and
CallableStatement
parameters with the exclusion of parameters set using
setBytes()
,
setBinaryStream()
,
setAsciiStream()
,
setUnicodeStream()
and
setBlob()
.
Prior to MySQL Server 4.1, Connector/J supported a single
character encoding per connection, which could either be
automatically detected from the server configuration, or could
be configured by the user through the
"useUnicode"
and "
characterEncoding
" properties.
Starting with MySQL Server 4.1, Connector/J supports a single
character encoding between client and server, and any number of
character encodings for data returned by the server to the
client in ResultSets
.
The character encoding between client and server is
automatically detected upon connection. The encoding used by the
driver is specified on the server via the configuration variable
'
character_set
' for server versions older than 4.1.0 and '
character_set_server
' for server versions 4.1.0 and newer. See the
"Server
Character Set and Collation" section in the MySQL server
manual for more information.
To override the automatically-detected encoding on the client
side, use the
characterEncoding
property in the URL used to connect to the server.
When specifying character encodings on the client side, Java-style names should be used. The following table lists Java-style names for MySQL character sets:
Table 26.4. MySQL to Java Encoding Name Translations
MySQL Character Set Name | Java-Style Character Encoding Name |
---|---|
usa7 | US-ASCII |
big5 | Big5 |
gbk | GBK |
sjis | SJIS (or Cp932 or MS932 for MySQL Server < 4.1.11) |
cp932 | Cp932 or MS932 (MySQL Server > 4.1.11) |
gb2312 | EUC_CN |
ujis | EUC_JP |
euc_kr | EUC_KR |
latin1 | ISO8859_1 |
latin1_de | ISO8859_1 |
german1 | ISO8859_1 |
danish | ISO8859_1 |
latin2 | ISO8859_2 |
czech | ISO8859_2 |
hungarian | ISO8859_2 |
croat | ISO8859_2 |
greek | ISO8859_7 |
hebrew | ISO8859_8 |
latin5 | ISO8859_9 |
latvian | ISO8859_13 |
latvian1 | ISO8859_13 |
estonia | ISO8859_13 |
dos | Cp437 |
pclatin2 | Cp852 |
cp866 | Cp866 |
koi8_ru | KOI8_R |
tis620 | TIS620 |
win1250 | Cp1250 |
win1250ch | Cp1250 |
win1251 | Cp1251 |
cp1251 | Cp1251 |
win1251ukr | Cp1251 |
cp1257 | Cp1257 |
macroman | MacRoman |
macce | MacCentralEurope |
utf8 | UTF-8 |
ucs2 | UnicodeBig |
Do not issue the query 'set names' with Connector/J, as the driver will not detect that the character set has changed, and will continue to use the character set detected during the initial connection setup.
To allow multiple character sets to be sent from the client, the
"UTF-8" encoding should be used, either by configuring "utf8" as
the default server character set, or by configuring the JDBC
driver to use "UTF-8" through the
characterEncoding
property.
SSL in MySQL Connector/J encrypts all data (other than the initial handshake) between the JDBC driver and the server. The performance penalty for enabling SSL is an increase in query processing time between 35% and 50%, depending on the size of the query, and the amount of data it returns.
For SSL Support to work, you must have the following:
A JDK that includes JSSE (Java Secure Sockets Extension), like JDK-1.4.1 or newer. SSL does not currently work with a JDK that you can add JSSE to, like JDK-1.2.x or JDK-1.3.x due to the following JSSE bug: http://developer.java.sun.com/developer/bugParade/bugs/4273544.html
A MySQL server that supports SSL and has been compiled and configured to do so, which is MySQL-4.0.4 or later, see: http://www.mysql.com/doc/en/Secure_connections.html
A client certificate (covered later in this section)
You will first need to import the MySQL server CA Certificate into a Java truststore. A sample MySQL server CA Certificate is located in the 'SSL' subdirectory of the MySQL source distribution. This is what SSL will use to determine if you are communicating with a secure MySQL server.
To use Java's 'keytool' to create a truststore in the current directory , and import the server's CA certificate ('cacert.pem'), you can do the following (assuming that'keytool' is in your path. It's located in the 'bin' subdirectory of your JDK or JRE):
shell> keytool -import -alias mysqlServerCACert -file cacert.pem -keystore truststore
Keytool will respond with the following information:
Enter keystore password: ********* Owner: [email protected], CN=Walrus, O=MySQL AB, L=Orenburg, ST=Some -State, C=RU Issuer: [email protected], CN=Walrus, O=MySQL AB, L=Orenburg, ST=Som e-State, C=RU Serial number: 0 Valid from: Fri Aug 02 16:55:53 CDT 2002 until: Sat Aug 02 16:55:53 CDT 2003 Certificate fingerprints: MD5: 61:91:A0:F2:03:07:61:7A:81:38:66:DA:19:C4:8D:AB SHA1: 25:77:41:05:D5:AD:99:8C:14:8C:CA:68:9C:2F:B8:89:C3:34:4D:6C Trust this certificate? [no]: yes Certificate was added to keystore
You will then need to generate a client certificate, so that the MySQL server knows that it is talking to a secure client:
shell> keytool -genkey -keyalg rsa -alias mysqlClientCertificate -keystore keystore
Keytool will prompt you for the following information, and create a keystore named 'keystore' in the current directory.
You should respond with information that is appropriate for your situation:
Enter keystore password: ********* What is your first and last name? [Unknown]: Matthews What is the name of your organizational unit? [Unknown]: Software Development What is the name of your organization? [Unknown]: MySQL AB What is the name of your City or Locality? [Unknown]: Flossmoor What is the name of your State or Province? [Unknown]: IL What is the two-letter country code for this unit? [Unknown]: US Is <CN=Matthews, OU=Software Development, O=MySQL AB, L=Flossmoor, ST=IL, C=US> correct? [no]: y Enter key password for <mysqlClientCertificate> (RETURN if same as keystore password):
Finally, to get JSSE to use the keystore and truststore that you have generated, you need to set the following system properties when you start your JVM, replacing 'path_to_keystore_file' with the full path to the keystore file you created, 'path_to_truststore_file' with the path to the truststore file you created, and using the appropriate password values for each property.
-Djavax.net.ssl.keyStore=path_to_keystore_file -Djavax.net.ssl.keyStorePassword=********* -Djavax.net.ssl.trustStore=path_to_truststore_file -Djavax.net.ssl.trustStorePassword=*********
You will also need to set 'useSSL' to 'true' in your connection parameters for MySQL Connector/J, either by adding 'useSSL=true' to your URL, or by setting the property 'useSSL' to 'true' in the java.util.Properties instance you pass to DriverManager.getConnection().
You can test that SSL is working by turning on JSSE debugging (as detailed below), and look for the following key events:
... *** ClientHello, v3.1 RandomCookie: GMT: 1018531834 bytes = { 199, 148, 180, 215, 74, 12, 54, 244, 0, 168, 55, 103, 215, 64, 16, 138, 225, 190, 132, 153, 2, 217, 219, 239, 202, 19, 121, 78 } Session ID: {} Cipher Suites: { 0, 5, 0, 4, 0, 9, 0, 10, 0, 18, 0, 19, 0, 3, 0, 17 } Compression Methods: { 0 } *** [write] MD5 and SHA1 hashes: len = 59 0000: 01 00 00 37 03 01 3D B6 90 FA C7 94 B4 D7 4A 0C ...7..=.......J. 0010: 36 F4 00 A8 37 67 D7 40 10 8A E1 BE 84 99 02 D9 6...7g.@........ 0020: DB EF CA 13 79 4E 00 00 10 00 05 00 04 00 09 00 ....yN.......... 0030: 0A 00 12 00 13 00 03 00 11 01 00 ........... main, WRITE: SSL v3.1 Handshake, length = 59 main, READ: SSL v3.1 Handshake, length = 74 *** ServerHello, v3.1 RandomCookie: GMT: 1018577560 bytes = { 116, 50, 4, 103, 25, 100, 58, 202, 79, 185, 178, 100, 215, 66, 254, 21, 83, 187, 190, 42, 170, 3, 132, 110, 82, 148, 160, 92 } Session ID: {163, 227, 84, 53, 81, 127, 252, 254, 178, 179, 68, 63, 182, 158, 30, 11, 150, 79, 170, 76, 255, 92, 15, 226, 24, 17, 177, 219, 158, 177, 187, 143} Cipher Suite: { 0, 5 } Compression Method: 0 *** %% Created: [Session-1, SSL_RSA_WITH_RC4_128_SHA] ** SSL_RSA_WITH_RC4_128_SHA [read] MD5 and SHA1 hashes: len = 74 0000: 02 00 00 46 03 01 3D B6 43 98 74 32 04 67 19 64 ...F..=.C.t2.g.d 0010: 3A CA 4F B9 B2 64 D7 42 FE 15 53 BB BE 2A AA 03 :.O..d.B..S..*.. 0020: 84 6E 52 94 A0 5C 20 A3 E3 54 35 51 7F FC FE B2 .nR..\ ..T5Q.... 0030: B3 44 3F B6 9E 1E 0B 96 4F AA 4C FF 5C 0F E2 18 .D?.....O.L.\... 0040: 11 B1 DB 9E B1 BB 8F 00 05 00 .......... main, READ: SSL v3.1 Handshake, length = 1712 ...
JSSE provides debugging (to STDOUT) when you set the following system property: -Djavax.net.debug=all This will tell you what keystores and truststores are being used, as well as what is going on during the SSL handshake and certificate exchange. It will be helpful when trying to determine what is not working when trying to get an SSL connection to happen.
Starting with Connector/J 3.1.7, we've made available a variant
of the driver that will automatically send queries to a
read/write master, or a failover or round-robin loadbalanced set
of slaves based on the state of
Connection.getReadOnly()
.
An application signals that it wants a transaction to be
read-only by calling
Connection.setReadOnly(true)
, this
"replication-aware" connection will use one of the slave
connections, which are load-balanced per-vm using a round-robin
scheme (a given connection is “sticky” to a slave
unless that slave is removed from service). If you have a write
transaction, or if you have a read that is "time-sensitive"
(remember, replication in MySQL is asynchronous), set the
connection to be not read-only, by calling
Connection.setReadOnly(false)
and the
driver will ensure that further calls are sent to the
“master” MySQL server. The driver takes care of
propagating the current state of autocommit, isolation level,
and catalog between all of the connections that it uses to
accomplish this load balancing functionality.
To enable this functionality, use the "
com.mysql.jdbc.ReplicationDriver
" class
when configuring your application server's connection pool or
when creating an instance of a JDBC driver for your standalone
application. Because it accepts the same URL format as the
standard MySQL JDBC driver,
ReplicationDriver
does not currently work
with java.sql.DriverManager
-based
connection creation unless it is the only MySQL JDBC driver
registered with the DriverManager
.
Here is a short, simple example of how ReplicationDriver might be used in a standalone application.
import java.sql.Connection; import java.sql.ResultSet; import java.util.Properties; import com.mysql.jdbc.ReplicationDriver; public class ReplicationDriverDemo { public static void main(String[] args) throws Exception { ReplicationDriver driver = new ReplicationDriver(); Properties props = new Properties(); // We want this for failover on the slaves props.put("autoReconnect", "true"); // We want to load balance between the slaves props.put("roundRobinLoadBalance", "true"); props.put("user", "foo"); props.put("password", "bar"); // // Looks like a normal MySQL JDBC url, with a comma-separated list // of hosts, the first being the 'master', the rest being any number // of slaves that the driver will load balance against // Connection conn = driver.connect("jdbc:mysql://master,slave1,slave2,slave3/test", props); // // Perform read/write work on the master // by setting the read-only flag to "false" // conn.setReadOnly(false); conn.setAutoCommit(false); conn.createStatement().executeUpdate("UPDATE some_table ...."); conn.commit(); // // Now, do a query from a slave, the driver automatically picks one // from the list // conn.setReadOnly(true); ResultSet rs = conn.createStatement().executeQuery("SELECT a,b,c FROM some_other_table"); ....... } }
This section describes how to use Connector/J in several contexts.
This section provides general background on J2EE concepts that pertain to use of Connector/J.
Connection pooling is a technique of creating and managing a pool of connections that are ready for use by any thread that needs them.
This technique of “pooling” connections is based on the fact that most applications only need a thread to have access to a JDBC connection when they are actively processing a transaction, which usually take only milliseconds to complete. When not processing a transaction, the connection would otherwise sit idle. Instead, connection pooling allows the idle connection to be used by some other thread to do useful work.
In practice, when a thread needs to do work against a MySQL or other database with JDBC, it requests a connection from the pool. When the thread is finished using the connection, it returns it to the pool, so that it may be used by any other threads that want to use it.
When the connection is "loaned out" from the pool, it is used exclusively by the thread that requested it. From a programming point of view, it is the same as if your thread called DriverManager.getConnection() every time it needed a JDBC connection, however with connection pooling, your thread may end up using either a new, or already-existing connection.
Connection pooling can greatly increase the performance of your Java application, while reducing overall resource usage. The main benefits to connection pooling are:
Reduced connection creation time
Although this is not usually an issue with the quick connection setup that MySQL offers compared to other databases, creating new JDBC connections still incurs networking and JDBC driver overhead that will be avoided if connections are "recycled."
Simplified programming model
When using connection pooling, each individual thread can act as though it has created its own JDBC connection, allowing you to use straight-forward JDBC programming techniques.
Controlled resource usage
If you don't use connection pooling, and instead create a new connection every time a thread needs one, your application's resource usage can be quite wasteful and lead to unpredictable behavior under load.
Remember that each connection to MySQL has overhead (memory, CPU, context switches, and so forth) on both the client and server side. Every connection limits how many resources there are available to your application as well as the MySQL server. Many of these resources will be used whether or not the connection is actually doing any useful work!
Connection pools can be tuned to maximize performance, while keeping resource utilization below the point where your application will start to fail rather than just run slower.
Luckily, Sun has standardized the concept of connection pooling in JDBC through the JDBC-2.0 "Optional" interfaces, and all major application servers have implementations of these APIs that work fine with MySQL Connector/J.
Generally, you configure a connection pool in your application server configuration files, and access it via the Java Naming and Directory Interface (JNDI). The following code shows how you might use a connection pool from an application deployed in a J2EE application server:
Example 26.12. Using a Connection Pool with a J2EE Application Server
import java.sql.Connection; import java.sql.SQLException; import java.sql.Statement; import javax.naming.InitialContext; import javax.sql.DataSource; public class MyServletJspOrEjb { public void doSomething() throws Exception { /* * Create a JNDI Initial context to be able to * lookup the DataSource * * In production-level code, this should be cached as * an instance or static variable, as it can * be quite expensive to create a JNDI context. * * Note: This code only works when you are using servlets * or EJBs in a J2EE application server. If you are * using connection pooling in standalone Java code, you * will have to create/configure datasources using whatever * mechanisms your particular connection pooling library * provides. */ InitialContext ctx = new InitialContext(); /* * Lookup the DataSource, which will be backed by a pool * that the application server provides. DataSource instances * are also a good candidate for caching as an instance * variable, as JNDI lookups can be expensive as well. */ DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/MySQLDB"); /* * The following code is what would actually be in your * Servlet, JSP or EJB 'service' method...where you need * to work with a JDBC connection. */ Connection conn = null; Statement stmt = null; try { conn = ds.getConnection(); /* * Now, use normal JDBC programming to work with * MySQL, making sure to close each resource when you're * finished with it, which allows the connection pool * resources to be recovered as quickly as possible */ stmt = conn.createStatement(); stmt.execute("SOME SQL QUERY"); stmt.close(); stmt = null; conn.close(); conn = null; } finally { /* * close any jdbc instances here that weren't * explicitly closed during normal code path, so * that we don't 'leak' resources... */ if (stmt != null) { try { stmt.close(); } catch (sqlexception sqlex) { // ignore -- as we can't do anything about it here } stmt = null; } if (conn != null) { try { conn.close(); } catch (sqlexception sqlex) { // ignore -- as we can't do anything about it here } conn = null; } } } }
As shown in the example above, after obtaining the JNDI InitialContext, and looking up the DataSource, the rest of the code should look familiar to anyone who has done JDBC programming in the past.
The most important thing to remember when using connection pooling is to make sure that no matter what happens in your code (exceptions, flow-of-control, and so forth), connections, and anything created by them (such as statements or result sets) are closed, so that they may be re-used, otherwise they will be "stranded," which in the best case means that the MySQL server resources they represent (such as buffers, locks, or sockets) may be tied up for some time, or worst case, may be tied up forever.
What's the Best Size for my Connection Pool?
As with all other configuration rules-of-thumb, the answer is "It depends." Although the optimal size depends on anticipated load and average database transaction time, the optimum connection pool size is smaller than you might expect. If you take Sun's Java Petstore blueprint application for example, a connection pool of 15-20 connections can serve a relatively moderate load (600 concurrent users) using MySQL and Tomcat with response times that are acceptable.
To correctly size a connection pool for your application, you should create load test scripts with tools such as Apache JMeter or The Grinder, and load test your application.
An easy way to determine a starting point is to configure your connection pool's maximum number of connections to be "unbounded," run a load test, and measure the largest amount of concurrently used connections. You can then work backward from there to determine what values of minimum and maximum pooled connections give the best performance for your particular application.
The following instructions are based on the instructions for Tomcat-5.x, available at http://jakarta.apache.org/tomcat/tomcat-5.0-doc/jndi-datasource-examples-howto.html which is current at the time this document was written.
First, install the .jar file that comes with Connector/J in
$CATALINA_HOME/common/lib
so that it is
available to all applications installed in the container.
Next, Configure the JNDI DataSource by adding a declaration
resource to $CATALINA_HOME/conf/server.xml
in the context that defines your web application:
<Context ....> ... <Resource name="jdbc/MySQLDB" auth="Container" type="javax.sql.DataSource"/> <!-- The name you used above, must match _exactly_ here! The connection pool will be bound into JNDI with the name "java:/comp/env/jdbc/MySQLDB" --> <ResourceParams name="jdbc/MySQLDB"> <parameter> <name>factory</name> <value>org.apache.commons.dbcp.BasicDataSourceFactory</value> </parameter> <!-- Don't set this any higher than max_connections on your MySQL server, usually this should be a 10 or a few 10's of connections, not hundreds or thousands --> <parameter> <name>maxActive</name> <value>10</value> </parameter> <!-- You don't want to many idle connections hanging around if you can avoid it, only enough to soak up a spike in the load --> <parameter> <name>maxIdle</name> <value>5</value> </parameter> <!-- Don't use autoReconnect=true, it's going away eventually and it's a crutch for older connection pools that couldn't test connections. You need to decide if your application is supposed to deal with SQLExceptions (hint, it should), and how much of a performance penalty you're willing to pay to ensure 'freshness' of the connection --> <parameter> <name>validationQuery</name> <value>SELECT 1</value> </parameter> <!-- The most conservative approach is to test connections before they're given to your application. For most applications this is okay, the query used above is very small and takes no real server resources to process, other than the time used to traverse the network. If you have a high-load application you'll need to rely on something else. --> <parameter> <name>testOnBorrow</name> <value>true</value> </parameter> <!-- Otherwise, or in addition to testOnBorrow, you can test while connections are sitting idle --> <parameter> <name>testWhileIdle</name> <value>true</value> </parameter> <!-- You have to set this value, otherwise even though you've asked connections to be tested while idle, the idle evicter thread will never run --> <parameter> <name>timeBetweenEvictionRunsMillis</name> <value>10000</value> </parameter> <!-- Don't allow connections to hang out idle too long, never longer than what wait_timeout is set to on the server...A few minutes or even fraction of a minute is sometimes okay here, it depends on your application and how much spikey load it will see --> <parameter> <name>minEvictableIdleTimeMillis</name> <value>60000</value> </parameter> <!-- Username and password used when connecting to MySQL --> <parameter> <name>username</name> <value>someuser</value> </parameter> <parameter> <name>password</name> <value>somepass</value> </parameter> <!-- Class name for the Connector/J driver --> <parameter> <name>driverClassName</name> <value>com.mysql.jdbc.Driver</value> </parameter> <!-- The JDBC connection url for connecting to MySQL, notice that if you want to pass any other MySQL-specific parameters you should pass them here in the URL, setting them using the parameter tags above will have no effect, you will also need to use & to separate parameter values as the ampersand is a reserved character in XML --> <parameter> <name>url</name> <value>jdbc:mysql://localhost:3306/test</value> </parameter> </ResourceParams> </Context>
In general, you should follow the installation instructions that come with your version of Tomcat, as the way you configure datasources in Tomcat changes from time-to-time, and unfortunately if you use the wrong syntax in your XML file, you will most likely end up with an exception similar to the following:
Error: java.sql.SQLException: Cannot load JDBC driver class 'null ' SQL state: null
These instructions cover JBoss-4.x. To make the JDBC driver
classes available to the application server, copy the .jar file
that comes with Connector/J to the lib
directory for your server configuration (which is usually called
"default
"). Then, in the same configuration
directory, in the subdirectory named “deploy,”
create a datasource configuration file that ends with "-ds.xml",
which tells JBoss to deploy this file as a JDBC Datasource. The
file should have the following contents:
<datasources> <local-tx-datasource> <!-- This connection pool will be bound into JNDI with the name "java:/MySQLDB" --> <jndi-name>MySQLDB</jndi-name> <connection-url>jdbc:mysql://localhost:3306/dbname</connection-url> <driver-class>com.mysql.jdbc.Driver</driver-class> <user-name>user</user-name> <password>pass</password> <min-pool-size>5</min-pool-size> <!-- Don't set this any higher than max_connections on your MySQL server, usually this should be a 10 or a few 10's of connections, not hundreds or thousands --> <max-pool-size>20</max-pool-size> <!-- Don't allow connections to hang out idle too long, never longer than what wait_timeout is set to on the server...A few minutes is usually okay here, it depends on your application and how much spikey load it will see --> <idle-timeout-minutes>5</idle-timeout-minutes> <!-- If you're using Connector/J 3.1.8 or newer, you can use our implementation of these to increase the robustness of the connection pool. --> <exception-sorter-class-name>com.mysql.jdbc.integration.jboss.ExtendedMysqlExceptionSorter</exception-sorter-class-name> <valid-connection-checker-class-name>com.mysql.jdbc.integration.jboss.MysqlValidConnectionChecker</valid-connection-checker-class-name> </local-tx-datasource> </datasources>
This section describes how to solve problems that you may encounter when using Connector/J.
There are a few issues that seem to be commonly encountered often by users of MySQL Connector/J. This section deals with their symptoms, and their resolutions.
27.3.5.1.1:
Question:
When I try to connect to the database with MySQL Connector/J, I get the following exception:
SQLException: Server configuration denies access to data source SQLState: 08001 VendorError: 0
What's going on? I can connect just fine with the MySQL command-line client.
Answer:
MySQL Connector/J must use TCP/IP sockets to connect to MySQL, as Java does not support Unix Domain Sockets. Therefore, when MySQL Connector/J connects to MySQL, the security manager in MySQL server will use its grant tables to determine whether or not the connection should be allowed.
You must add grants to allow this to happen. The following is an example of how to do this (but not the most secure).
From the mysql command-line client, logged in as a user that can grant privileges, issue the following command:
GRANT ALL PRIVILEGES ON [dbname].* to '[user]'@'[hostname]' identified by '[password]'
replacing [dbname] with the name of your database, [user] with the user name, [hostname] with the host that MySQL Connector/J will be connecting from, and [password] with the password you want to use. Be aware that RedHat Linux is broken with respect to the hostname portion for the case when you are connecting from localhost. You need to use "localhost.localdomain" for the [hostname] value in this case. Follow this by issuing the "FLUSH PRIVILEGES" command.
Testing your connectivity with the
mysql command-line client will not
work unless you add the --host
flag,
and use something other than
localhost
for the host. The
mysql command-line client will use
Unix domain sockets if you use the special hostname
localhost
. If you are testing
connectivity to localhost
, use
127.0.0.1
as the hostname instead.
If you don't understand what the 'GRANT' command does, or how it works, you should read and understand the 'General Security Issues and the MySQL Access Privilege System' section of the MySQL manual before attempting to change privileges.
Changing privileges and permissions improperly in MySQL can potentially cause your server installation to not have optimal security properties.
27.3.5.1.2:
Question:
My application throws an SQLException 'No Suitable Driver'. Why is this happening?
Answer:
One of two things are happening. Either the driver is not in your CLASSPATH or your URL format is incorrect (see the Section 26.3.2, “Installing Connector/J” section.).
27.3.5.1.3:
Question:
I'm trying to use MySQL Connector/J in an applet or application and I get an exception similar to:
SQLException: Cannot connect to MySQL server on host:3306. Is there a MySQL server running on the machine/port you are trying to connect to? (java.security.AccessControlException) SQLState: 08S01 VendorError: 0
Answer:
Either you're running an Applet, your MySQL server has been installed with the "--skip-networking" option set, or your MySQL server has a firewall sitting in front of it.
Applets can only make network connections back to the machine that runs the web server that served the .class files for the applet. This means that MySQL must run on the same machine (or you must have some sort of port re-direction) for this to work. This also means that you will not be able to test applets from your local file system, you must always deploy them to a web server.
MySQL Connector/J can only communicate with MySQL using TCP/IP, as Java does not support Unix domain sockets. TCP/IP communication with MySQL might be affected if MySQL was started with the "--skip-networking" flag, or if it is firewalled.
If MySQL has been started with the "--skip-networking"
option set (the Debian Linux package of MySQL server does
this for example), you need to comment it out in the file
/etc/mysql/my.cnf or /etc/my.cnf. Of course your my.cnf
file might also exist in the data
directory of your MySQL server, or anywhere else
(depending on how MySQL was compiled for your system).
Binaries created by MySQL AB always look in /etc/my.cnf
and [datadir]/my.cnf. If your MySQL server has been
firewalled, you will need to have the firewall configured
to allow TCP/IP connections from the host where your Java
code is running to the MySQL server on the port that MySQL
is listening to (by default, 3306).
27.3.5.1.4:
Question:
I have a servlet/application that works fine for a day, and then stops working overnight
Answer:
MySQL closes connections after 8 hours of inactivity. You either need to use a connection pool that handles stale connections or use the "autoReconnect" parameter (see "Developing Applications with MySQL Connector/J").
Also, you should be catching SQLExceptions in your application and dealing with them, rather than propagating them all the way until your application exits, this is just good programming practice. MySQL Connector/J will set the SQLState (see java.sql.SQLException.getSQLState() in your APIDOCS) to "08S01" when it encounters network-connectivity issues during the processing of a query. Your application code should then attempt to re-connect to MySQL at this point.
The following (simplistic) example shows what code that can handle these exceptions might look like:
Example 26.13. Example of transaction with retry logic
public void doBusinessOp() throws SQLException { Connection conn = null; Statement stmt = null; ResultSet rs = null; // // How many times do you want to retry the transaction // (or at least _getting_ a connection)? // int retryCount = 5; boolean transactionCompleted = false; do { try { conn = getConnection(); // assume getting this from a // javax.sql.DataSource, or the // java.sql.DriverManager conn.setAutoCommit(false); // // Okay, at this point, the 'retry-ability' of the // transaction really depends on your application logic, // whether or not you're using autocommit (in this case // not), and whether you're using transacational storage // engines // // For this example, we'll assume that it's _not_ safe // to retry the entire transaction, so we set retry count // to 0 at this point // // If you were using exclusively transaction-safe tables, // or your application could recover from a connection going // bad in the middle of an operation, then you would not // touch 'retryCount' here, and just let the loop repeat // until retryCount == 0. // retryCount = 0; stmt = conn.createStatement(); String query = "SELECT foo FROM bar ORDER BY baz"; rs = stmt.executeQuery(query); while (rs.next()) { } rs.close(); rs = null; stmt.close(); stmt = null; conn.commit(); conn.close(); conn = null; transactionCompleted = true; } catch (SQLException sqlEx) { // // The two SQL states that are 'retry-able' are 08S01 // for a communications error, and 40001 for deadlock. // // Only retry if the error was due to a stale connection, // communications problem or deadlock // String sqlState = sqlEx.getSQLState(); if ("08S01".equals(sqlState) || "40001".equals(sqlState)) { retryCount--; } else { retryCount = 0; } } finally { if (rs != null) { try { rs.close(); } catch (SQLException sqlEx) { // You'd probably want to log this . . . } } if (stmt != null) { try { stmt.close(); } catch (SQLException sqlEx) { // You'd probably want to log this as well . . . } } if (conn != null) { try { // // If we got here, and conn is not null, the // transaction should be rolled back, as not // all work has been done try { conn.rollback(); } finally { conn.close(); } } catch (SQLException sqlEx) { // // If we got an exception here, something // pretty serious is going on, so we better // pass it up the stack, rather than just // logging it. . . throw sqlEx; } } } } while (!transactionCompleted && (retryCount > 0)); }
27.3.5.1.5:
Question:
I'm trying to use JDBC-2.0 updatable result sets, and I get an exception saying my result set is not updatable.
Answer:
Because MySQL does not have row identifiers, MySQL Connector/J can only update result sets that have come from queries on tables that have at least one primary key, the query must select every primary key and the query can only span one table (that is, no joins). This is outlined in the JDBC specification.
The normal place to report bugs is http://bugs.mysql.com/, which is the address for our bugs database. This database is public, and can be browsed and searched by anyone. If you log in to the system, you will also be able to enter new reports.
If you have found a sensitive security bug in MySQL, you can send email to [email protected].
Writing a good bug report takes patience, but doing it right the first time saves time both for us and for yourself. A good bug report, containing a full test case for the bug, makes it very likely that we will fix the bug in the next release.
This section will help you write your report correctly so that you don't waste your time doing things that may not help us much or at all.
If you have a repeatable bug report, please report it to the bugs database at http://bugs.mysql.com/.
Any bug that we are able to repeat has a high chance of being fixed in the next MySQL release.
To report other problems, you can use one of the MySQL mailing lists.
Remember that it is possible for us to respond to a message containing too much information, but not to one containing too little. People often omit facts because they think they know the cause of a problem and assume that some details don't matter.
A good principle is this: If you are in doubt about stating something, state it. It is faster and less troublesome to write a couple more lines in your report than to wait longer for the answer if we must ask you to provide information that was missing from the initial report.
The most common errors made in bug reports are (a) not including the version number of Connector/J or MySQL used, and (b) not fully describing the platform on which Connector/J is installed (including the JVM version, and the platform type and version number that MySQL itself is installed on).
This is highly relevant information, and in 99 cases out of 100, the bug report is useless without it. Very often we get questions like, ``Why doesn't this work for me?'' Then we find that the feature requested wasn't implemented in that MySQL version, or that a bug described in a report has already been fixed in newer MySQL versions.
Sometimes the error is platform-dependent; in such cases, it is next to impossible for us to fix anything without knowing the operating system and the version number of the platform.
If at all possible, you should create a repeatable, stanalone testcase that doesn't involve any third-party classes.
To streamline this process, we ship a base class for testcases
with Connector/J, named
'com.mysql.jdbc.util.BaseBugReport
'. To
create a testcase for Connector/J using this class, create your
own class that inherits from
com.mysql.jdbc.util.BaseBugReport
and
override the methods setUp()
,
tearDown()
and
runTest
().
In the setUp()
method, create code that
creates your tables, and populates them with any data needed to
demonstrate the bug.
In the runTest
() method, create code
that demonstrates the bug using the tables and data you created
in the setUp
method.
In the tearDown()
method, drop any
tables you created in the setUp()
method.
In any of the above three methods, you should use one of the
variants of the getConnection
() method
to create a JDBC connection to MySQL:
getConnection() - Provides a connection to the JDBC URL specified in getUrl(). If a connection already exists, that connection is returned, otherwise a new connection is created.
getNewConnection() - Use this if you need to get a new connection for your bug report (i.e. there's more than one connection involved).
getConnection(String url) - Returns a connection using the given URL.
getConnection(String url, Properties props) - Returns a connection using the given URL and properties.
If you need to use a JDBC URL that is different than
'jdbc:mysql:///test', then override the method
getUrl()
as well.
Use the assertTrue(boolean expression)
and assertTrue(String failureMessage, boolean
expression)
methods to create conditions that must
be met in your testcase demonstrating the behavior you are
expecting (vs. the behavior you are observing, which is why you
are most likely filing a bug report).
Finally, create a main
() method that
creates a new instance of your testcase, and calls the
run
method:
public static void main(String[] args) throws Exception { new MyBugReport().run(); }
Once you have finished your testcase, and have verified that it demonstrates the bug you are reporting, upload it with your bug report to http://bugs.mysql.com/.
12-22-05 - Version 5.0.0-beta - XADataSource implemented (ported from 3.2 branch which won't be released as a product). Use "com.mysql.jdbc.jdbc2.optional.MysqlXADataSource" as your datasource class name in your application server to utilize XA transactions in MySQL-5.0.10 and newer. - PreparedStatement.setString() didn't work correctly when sql_mode on server contained NO_BACKSLASH_ESCAPES, and no characters that needed escaping were present in the string. - Attempt detection of the MySQL type "BINARY" (it's an alias, so this isn't always reliable), and use the java.sql.Types.BINARY type mapping for it. - Moved -bin-g.jar file into separate "debug" subdirectory to avoid confusion. - Don't allow .setAutoCommit(true), or .commit() or .rollback() on an XA-managed connection as-per the JDBC specification. - If the connection "useTimezone" is set to "true", then also respect timezone conversions in escape-processed string literals (e.g. "{ts ...}" and "{t ...}"). - Return original column name for RSMD.getColumnName() if the column was aliased, alias name for .getColumnLabel() (if aliased), and original table name for .getTableName(). Note this only works for MySQL-4.1 and newer, as older servers don't make this information available to clients. - Setting "useJDBCCompliantTimezoneShift=true" (it's not the default) causes the driver to use GMT for _all_ TIMESTAMP/DATETIME timezones, and the current VM timezone for any other type that refers to timezones. This feature can not be used when "useTimezone=true" to convert between server and client timezones. - Add one level of indirection of internal representation of CallableStatement parameter metadata to avoid class not found issues on JDK-1.3 for ParameterMetadata interface (which doesn't exist prior to JDBC-3.0). - Added unit tests for XADatasource, as well as friendlier exceptions for XA failures compared to the "stock" XAException (which has no messages). - Fixed BUG#14279 - Idle timeouts cause XAConnections to whine about rolling themselves back - Added support for Connector/MXJ integration via url subprotocol "jdbc:mysql:mxj://....". - Moved all SQLException constructor usage to a factory in SQLError (ground-work for JDBC-4.0 SQLState-based exception classes). - Removed Java5-specific calls to BigDecimal constructor (when result set value is '', (int)0 was being used as an argument in-directly via method return value. This signature doesn't exist prior to Java5.) - Moved all SQLException creation to a factory method in SQLError, groundwork for JDBC-4.0 SQLState class-based exceptions. - Added service-provider entry to META-INF/services/java.sql.Driver for JDBC-4.0 support. - Return "[VAR]BINARY" for RSMD.getColumnTypeName() when that is actually the type, and it can be distinguished (MySQL-4.1 and newer). - When fix for BUG#14562 was merged from 3.1.12, added functionality for CallableStatement's parameter metadata to return correct information for .getParameterClassName(). - Fuller synchronization of Connection to avoid deadlocks when using multithreaded frameworks that multithread a single connection (usually not recommended, but the JDBC spec allows it anyways), part of fix to BUG#14972). - Implementation of Statement.cancel() and Statement.setQueryTimeout(). Both require MySQL-5.0.0 or newer server, require a separate connection to issue the "KILL QUERY" command, and in the case of setQueryTimeout() creates an additional thread to handle the timeout functionality. Note: Failures to cancel the statement for setQueryTimeout() may manifest themselves as RuntimeExceptions rather than failing silently, as there is currently no way to unblock the thread that is executing the query being cancelled due to timeout expiration and have it throw the exception instead. xx-xx-05 - Version 3.1.13 - Fixed BUG#15464 - INOUT parameter does not store IN value. - Fixed BUG#14609 - Exception thrown for new decimal type when using updatable result sets. - Fixed BUG#15544, no "dos" character set in MySQL > 4.1.0 - Fixed BUG#15383 - PreparedStatement.setObject() serializes BigInteger as object, rather than sending as numeric value (and is thus not complementary to .getObject() on an UNSIGNED LONG type). - Fixed BUG#11874 - ResultSet.getShort() for UNSIGNED TINYINT returned wrong values. - Fixed BUG#15676 - lib-nodist directory missing from package breaks out-of-box build - Fixed BUG#15854 - DBMD.getColumns() returns wrong type for BIT. 11-30-05 - Version 3.1.12 - Fixed client-side prepared statement bug with embedded ? inside quoted identifiers (it was recognized as a placeholder, when it was not). - Don't allow executeBatch() for CallableStatements with registered OUT/INOUT parameters (JDBC compliance). - Fall back to platform-encoding for URLDecoder.decode() when parsing driver URL properties if the platform doesn't have a two-argument version of this method. - Fixed BUG#14562 - Java type conversion may be incorrect for mediumint. - Added configuration property "useGmtMillisForDatetimes" which when set to true causes ResultSet.getDate(), .getTimestamp() to return correct millis-since GMT when .getTime() is called on the return value (currently default is "false" for legacy behavior). - Fixed DatabaseMetaData.stores*Identifiers(): * if lower_case_table_names=0 (on server): storesLowerCaseIdentifiers() returns false storesLowerCaseQuotedIdentifiers() returns false storesMixedCaseIdentifiers() returns true storesMixedCaseQuotedIdentifiers() returns true storesUpperCaseIdentifiers() returns false storesUpperCaseQuotedIdentifiers() returns true * if lower_case_table_names=1 (on server): storesLowerCaseIdentifiers() returns true storesLowerCaseQuotedIdentifiers() returns true storesMixedCaseIdentifiers() returns false storesMixedCaseQuotedIdentifiers() returns false storesUpperCaseIdentifiers() returns false storesUpperCaseQuotedIdentifiers() returns true - Fixed BUG#14815 - DatabaseMetaData.getColumns() doesn't return TABLE_NAME correctly. - Fixed BUG#14909 - escape processor replaces quote character in quoted string with string delimiter. - Fixed BUG#12975 - OpenOffice expects DBMD.supportsIntegrityEnhancementFacility() to return "true" if foreign keys are supported by the datasource, even though this method also covers support for check constraints, which MySQL _doesn't_ have. Setting the configuration property "overrideSupportsIntegrityEnhancementFacility" to "true" causes the driver to return "true" for this method. - Added "com.mysql.jdbc.testsuite.url.default" system property to set default JDBC url for testsuite (to speed up bug resolution when I'm working in Eclipse). - Fixed BUG#14938 - Unable to initialize character set mapping tables (due to J2EE classloader differences). - Fixed BUG#14972 - Deadlock while closing server-side prepared statements from multiple threads sharing one connection. - Fixed BUG#12230 - logSlowQueries should give better info. - Fixed BUG#13775 - Extraneous sleep on autoReconnect. - Fixed BUG#15024 - Driver incorrectly closes streams passed as arguments to PreparedStatements. Reverts to legacy behavior by setting the JDBC configuration property "autoClosePStmtStreams" to "true" (also included in the 3-0-Compat configuration "bundle"). - Fixed BUG#13048 - maxQuerySizeToLog is not respected. Added logging of bound values for execute() phase of server-side prepared statements when profileSQL=true as well. - Fixed BUG#15065 - Usage advisor complains about unreferenced columns, even though they've been referenced. - Don't increase timeout for failover/reconnect (BUG#6577) - Process escape tokens in Connection.prepareStatement(...), fix for BUG#15141. You can disable this behavior by setting the JDBC URL configuration property "processEscapeCodesForPrepStmts" to "false". - Fixed BUG#13255 - Reconnect during middle of executeBatch() should not occur if autoReconnect is enabled. 10-07-05 - Version 3.1.11-stable - Fixed BUG#11629 - Spurious "!" on console when character encoding is "utf8". - Fixed statements generated for testcases missing ";" for "plain" statements. - Fixed BUG#11663 - Incorrect generation of testcase scripts for server-side prepared statements. - Fixed regression caused by fix for BUG#11552 that caused driver to return incorrect values for unsigned integers when those integers where within the range of the positive signed type. - Moved source code to svn repo. - Fixed BUG#11797 - Escape tokenizer doesn't respect stacked single quotes for escapes. - GEOMETRY type not recognized when using server-side prepared statements. - Fixed BUG#11879 -- ReplicationConnection won't switch to slave, throws "Catalog can't be null" exception. - Fixed BUG#12218, properties shared between master and slave with replication connection. - Fixed BUG#10630, Statement.getWarnings() fails with NPE if statement has been closed. - Only get char[] from SQL in PreparedStatement.ParseInfo() when needed. - Fixed BUG#12104 - Geometry types not handled with server-side prepared statements. - Fixed BUG#11614 - StringUtils.getBytes() doesn't work when using multibyte character encodings and a length in _characters_ is specified. - Fixed BUG#11798 - Pstmt.setObject(...., Types.BOOLEAN) throws exception. - Fixed BUG#11976 - maxPerformance.properties mis-spells "elideSetAutoCommits". - Fixed BUG#11575 -- DBMD.storesLower/Mixed/UpperIdentifiers() reports incorrect values for servers deployed on Windows. - Fixed BUG#11190 - ResultSet.moveToCurrentRow() fails to work when preceded by a call to ResultSet.moveToInsertRow(). - Fixed BUG#11115, VARBINARY data corrupted when using server-side prepared statements and .setBytes(). - Fixed BUG#12229 - explainSlowQueries hangs with server-side prepared statements. - Fixed BUG#11498 - Escape processor didn't honor strings demarcated with double quotes. - Lifted restriction of changing streaming parameters with server-side prepared statements. As long as _all_ streaming parameters were set before execution, .clearParameters() does not have to be called. (due to limitation of client/server protocol, prepared statements can not reset _individual_ stream data on the server side). - Reworked Field class, *Buffer, and MysqlIO to be aware of field lengths > Integer.MAX_VALUE. - Updated DBMD.supportsCorrelatedQueries() to return true for versions > 4.1, supportsGroupByUnrelated() to return true and getResultSetHoldability() to return HOLD_CURSORS_OVER_COMMIT. - Fixed BUG#12541 - Handling of catalog argument in DatabaseMetaData.getIndexInfo(), which also means changes to the following methods in DatabaseMetaData: - getBestRowIdentifier() - getColumns() - getCrossReference() - getExportedKeys() - getImportedKeys() - getIndexInfo() - getPrimaryKeys() - getProcedures() (and thus indirectly getProcedureColumns()) - getTables() The "catalog" argument in all of these methods now behaves in the following way: - Specifying NULL means that catalog will not be used to filter the results (thus all databases will be searched), unless you've set "nullCatalogMeansCurrent=true" in your JDBC URL properties. - Specifying "" means "current" catalog, even though this isn't quite JDBC spec compliant, it's there for legacy users. - Specifying a catalog works as stated in the API docs. - Made Connection.clientPrepare() available from "wrapped" connections in the jdbc2.optional package (connections built by ConnectionPoolDataSource instances). - Added Connection.isMasterConnection() for clients to be able to determine if a multi-host master/slave connection is connected to the first host in the list. - Fixed BUG#12753 - Tokenizer for "=" in URL properties was causing sessionVariables=.... to be parameterized incorrectly. - Fixed BUG#11781, foreign key information that is quoted is parsed incorrectly when DatabaseMetaData methods use that information. - The "sendBlobChunkSize" property is now clamped to "max_allowed_packet" with consideration of stream buffer size and packet headers to avoid PacketTooBigExceptions when "max_allowed_packet" is similar in size to the default "sendBlobChunkSize" which is 1M. - CallableStatement.clearParameters() now clears resources associated with INOUT/OUTPUT parameters as well as INPUT parameters. - Fixed BUG#12417 - Connection.prepareCall() is database name case-sensitive (on Windows systems). - Fixed BUG#12752 - Cp1251 incorrectly mapped to win1251 for servers newer than 4.0.x. - Fixed BUG#12970 - java.sql.Types.OTHER returned for BINARY and VARBINARY columns when using DatabaseMetaData.getColumns(). - ServerPreparedStatement.getBinding() now checks if the statement is closed before attempting to reference the list of parameter bindings, to avoid throwing a NullPointerException. - Fixed BUG#13277 - ResultSetMetaData from Statement.getGeneratedKeys() caused NullPointerExceptions to be thrown whenever a method that required a connection reference was called. - Backport of Field class, ResultSetMetaData.getColumnClassName(), and ResultSet.getObject(int) changes from 5.0 branch to fix behavior surrounding VARCHAR BINARY/VARBINARY and related types. - Fixed NullPointerException when converting "catalog" parameter in many DatabaseMetaDataMethods to byte[]s (for the result set) when the parameter is null. ("null" isn't technically allowed by the JDBC specification, but we've historically allowed it). - Backport of VAR[BINARY|CHAR] [BINARY] types detection from 5.0 branch. - Read response in MysqlIO.sendFileToServer(), even if the local file can't be opened, otherwise next query issued will fail, because it's reading the response to the empty LOAD DATA INFILE packet sent to the server. - Workaround for BUG#13374 - ResultSet.getStatement() on closed result set returns NULL (as per JDBC 4.0 spec, but not backward-compatible). Set the connection property "retainStatementAfterResultSetClose" to "true" to be able to retrieve a ResultSet's statement after the ResultSet has been closed via .getStatement() (the default is "false", to be JDBC-compliant and to reduce the chance that code using JDBC leaks Statement instances). - Fixed BUG#13453 - URL configuration parameters don't allow '&' or '=' in their values. The JDBC driver now parses configuration parameters as if they are encoded using the application/x-www-form-urlencoded format as specified by java.net.URLDecoder - http://java.sun.com/j2se/1.5.0/docs/api/java/net/URLDecoder.html If the '%' character is present in a configuration property, it must now be represented as %25, which is the encoded form of '%' when using application/x-www-form-urlencoded encoding. - The configuration property "sessionVariables" now allows you to specify variables that start with the "@" sign. - Fixed BUG#13043 - when 'gatherPerfMetrics' is enabled for servers older than 4.1.0, a NullPointerException is thrown from the constructor of ResultSet if the query doesn't use any tables. 06-23-05 - Version 3.1.10-stable - Fixed connecting without a database specified raised an exception in MysqlIO.changeDatabaseTo(). - Initial implemention of ParameterMetadata for PreparedStatement.getParameterMetadata(). Only works fully for CallableStatements, as current server-side prepared statements return every parameter as a VARCHAR type. 06-22-05 - Version 3.1.9-stable - Overhaul of character set configuration, everything now lives in a properties file. - Driver now correctly uses CP932 if available on the server for Windows-31J, CP932 and MS932 java encoding names, otherwise it resorts to SJIS, which is only a close approximation. Currently only MySQL-5.0.3 and newer (and MySQL-4.1.12 or .13, depending on when the character set gets backported) can reliably support any variant of CP932. - Fixed BUG#9064 - com.mysql.jdbc.PreparedStatement.ParseInfo does unnecessary call to toCharArray(). - Fixed Bug#10144 - Memory leak in ServerPreparedStatement if serverPrepare() fails. - Actually write manifest file to correct place so it ends up in the binary jar file. - Added "createDatabaseIfNotExist" property (default is "false"), which will cause the driver to ask the server to create the database specified in the URL if it doesn't exist. You must have the appropriate privileges for database creation for this to work. - Fixed BUG#10156 - Unsigned SMALLINT treated as signed for ResultSet.getInt(), fixed all cases for UNSIGNED integer values and server-side prepared statements, as well as ResultSet.getObject() for UNSIGNED TINYINT. - Fixed BUG#10155, double quotes not recognized when parsing client-side prepared statements. - Made enableStreamingResults() visible on com.mysql.jdbc.jdbc2.optional.StatementWrapper. - Made ServerPreparedStatement.asSql() work correctly so auto-explain functionality would work with server-side prepared statements. - Made JDBC2-compliant wrappers public in order to allow access to vendor extensions. - Cleaned up logging of profiler events, moved code to dump a profiler event as a string to com.mysql.jdbc.log.LogUtils so that third parties can use it. - DatabaseMetaData.supportsMultipleOpenResults() now returns true. The driver has supported this for some time, DBMD just missed that fact. - Fixed BUG#10310 - Driver doesn't support {?=CALL(...)} for calling stored functions. This involved adding support for function retrieval to DatabaseMetaData.getProcedures() and getProcedureColumns() as well. - Fixed BUG#10485, SQLException thrown when retrieving YEAR(2) with ResultSet.getString(). The driver will now always treat YEAR types as java.sql.Dates and return the correct values for getString(). Alternatively, the "yearIsDateType" connection property can be set to "false" and the values will be treated as SHORTs. - The datatype returned for TINYINT(1) columns when "tinyInt1isBit=true" (the default) can be switched between Types.BOOLEAN and Types.BIT using the new configuration property "transformedBitIsBoolean", which defaults to "false". If set to "false" (the default), DatabaseMetaData.getColumns() and ResultSetMetaData.getColumnType() will return Types.BOOLEAN for TINYINT(1) columns. If "true", Types.BOOLEAN will be returned instead. Irregardless of this configuration property, if "tinyInt1isBit" is enabled, columns with the type TINYINT(1) will be returned as java.lang.Boolean instances from ResultSet.getObject(..), and ResultSetMetaData.getColumnClassName() will return "java.lang.Boolean". - Fixed BUG#10496 - SQLException is thrown when using property "characterSetResults" with cp932 or eucjpms. - Reorganized directory layout, sources now in "src" folder, don't pollute parent directory when building, now output goes to "./build", distribution goes to "./dist". - Added support/bug hunting feature that generates .sql test scripts to STDERR when "autoGenerateTestcaseScript" is set to "true". - Fixed BUG#10850 - 0-length streams not sent to server when using server-side prepared statements. - Setting "cachePrepStmts=true" now causes the Connection to also cache the check the driver performs to determine if a prepared statement can be server-side or not, as well as caches server-side prepared statements for the lifetime of a connection. As before, the "prepStmtCacheSize" parameter controls the size of these caches. - Try to handle OutOfMemoryErrors more gracefully. Although not much can be done, they will in most cases close the connection they happened on so that further operations don't run into a connection in some unknown state. When an OOM has happened, any further operations on the connection will fail with a "Connection closed" exception that will also list the OOM exception as the reason for the implicit connection close event. - Don't send COM_RESET_STMT for each execution of a server-side prepared statement if it isn't required. - Driver detects if you're running MySQL-5.0.7 or later, and does not scan for "LIMIT ?[,?]" in statements being prepared, as the server supports those types of queries now. - Fixed BUG#11115, Varbinary data corrupted when using server-side prepared statements and ResultSet.getBytes(). - Connection.setCatalog() is now aware of the "useLocalSessionState" configuration property, which when set to true will prevent the driver from sending "USE ..." to the server if the requested catalog is the same as the current catalog. - Added the following configuration bundles, use one or many via the "useConfigs" configuration property: * maxPerformance -- maximum performance without being reckless * solarisMaxPerformance -- maximum performance for Solaris, avoids syscalls where it can * 3-0-Compat -- Compatibility with Connector/J 3.0.x functionality - Added "maintainTimeStats" configuration property (defaults to "true"), which tells the driver whether or not to keep track of the last query time and the last successful packet sent to the server's time. If set to false, removes two syscalls per query. - Fixed BUG#11259, autoReconnect ping causes exception on connection startup. - Fixed BUG#11360 Connector/J dumping query into SQLException twice - Fixed PreparedStatement.setClob() not accepting null as a parameter. - Fixed BUG#11411 - Production package doesn't include JBoss integration classes. - Removed nonsensical "costly type conversion" warnings when using usage advisor. 04-14-05 - Version 3.1.8-stable - Fixed DatabaseMetaData.getTables() returning views when they were not asked for as one of the requested table types. - Added support for new precision-math DECIMAL type in MySQL >= 5.0.3. - Fixed ResultSet.getTime() on a NULL value for server-side prepared statements throws NPE. - Made Connection.ping() a public method. - Fixed Bug#8868, DATE_FORMAT() queries returned as BLOBs from getObject(). - ServerPreparedStatements now correctly 'stream' BLOB/CLOB data to the server. You can configure the threshold chunk size using the JDBC URL property 'blobSendChunkSize' (the default is one megabyte). - BlobFromLocator now uses correct identifier quoting when generating prepared statements. - Server-side session variables can be preset at connection time by passing them as a comma-delimited list for the connection property 'sessionVariables'. - Fixed regression in ping() for users using autoReconnect=true. - Fixed BUG#9040 - PreparedStatement.addBatch() doesn't work with server-side prepared statements and streaming BINARY data. - Fixed BUG#8800 - DBMD.supportsMixedCase*Identifiers() returns wrong value on servers running on case-sensitive filesystems. - Fixed BUG#9206, can not use 'UTF-8' for characterSetResults configuration property. - Fixed BUG#9236, a continuation of BUG#8868, where functions used in queries that should return non-string types when resolved by temporary tables suddenly become opaque binary strings (work-around for server limitation). Also fixed fields with type of CHAR(n) CHARACTER SET BINARY to return correct/matching classes for RSMD.getColumnClassName() and ResultSet.getObject(). - Fixed BUG#8792 - DBMD.supportsResultSetConcurrency() not returning true for forward-only/read-only result sets (we obviously support this). - Fixed BUG#8803, 'DATA_TYPE' column from DBMD.getBestRowIdentifier() causes ArrayIndexOutOfBoundsException when accessed (and in fact, didn't return any value). - Check for empty strings ('') when converting char/varchar column data to numbers, throw exception if 'emptyStringsConvertToZero' configuration property is set to 'false' (for backward-compatibility with 3.0, it is now set to 'true' by default, but will most likely default to 'false' in 3.2). - Fixed BUG#9320 - PreparedStatement.getMetaData() inserts blank row in database under certain conditions when not using server-side prepared statements. - Connection.canHandleAsPreparedStatement() now makes 'best effort' to distinguish LIMIT clauses with placeholders in them from ones without in order to have fewer false positives when generating work-arounds for statements the server cannot currently handle as server-side prepared statements. - Fixed build.xml to not compile log4j logging if log4j not available. - Added support for the c3p0 connection pool's (http://c3p0.sf.net/) validation/connection checker interface which uses the lightweight 'COM_PING' call to the server if available. To use it, configure your c3p0 connection pool's 'connectionTesterClassName' property to use 'com.mysql.jdbc.integration.c3p0.MysqlConnectionTester'. - Better detection of LIMIT inside/outside of quoted strings so that the driver can more correctly determine whether a prepared statement can be prepared on the server or not. - Fixed BUG#9319 - Stored procedures with same name in different databases confuse the driver when it tries to determine parameter counts/types. - Added finalizers to ResultSet and Statement implementations to be JDBC spec-compliant, which requires that if not explicitly closed, these resources should be closed upon garbage collection. - Fixed BUG#9682 - Stored procedures with DECIMAL parameters with storage specifications that contained "," in them would fail. - PreparedStatement.setObject(int, Object, int type, int scale) now uses scale value for BigDecimal instances. - Fixed BUG#9704 - Statement.getMoreResults() could throw NPE when existing result set was .close()d. - The performance metrics feature now gathers information about number of tables referenced in a SELECT. - The logging system is now automatically configured. If the value has been set by the user, via the URL property "logger" or the system property "com.mysql.jdbc.logger", then use that, otherwise, autodetect it using the following steps: Log4j, if it's available, Then JDK1.4 logging, Then fallback to our STDERR logging. - Fixed BUG#9778, DBMD.getTables() shouldn't return tables if views are asked for, even if the database version doesn't support views. - Fixed driver not returning 'true' for '-1' when ResultSet.getBoolean() was called on result sets returned from server-side prepared statements. - Added a Manifest.MF file with implementation information to the .jar file. - More tests in Field.isOpaqueBinary() to distinguish opaque binary (i.e. fields with type CHAR(n) and CHARACTER SET BINARY) from output of various scalar and aggregate functions that return strings. - Fixed BUG#9917 - Should accept null for catalog (meaning use current) in DBMD methods, even though it's not JDBC-compliant for legacy's sake. Disable by setting connection property "nullCatalogMeansCurrent" to "false" (which will be the default value in C/J 3.2.x). - Fixed BUG#9769 - Should accept null for name patterns in DBMD (meaning "%"), even though it isn't JDBC compliant, for legacy's sake. Disable by setting connection property "nullNamePatternMatchesAll" to "false" (which will be the default value in C/J 3.2.x). 02-18-05 - Version 3.1.7-stable - Fixed BUG#7686, Timestamp key column data needed "_binary'" stripped for UpdatableResultSet.refreshRow(). - Fixed BUG#7715 - Timestamps converted incorrectly to strings with Server-side prepared statements and updatable result sets. - Detect new sql_mode variable in string form (it used to be integer) and adjust quoting method for strings appropriately. - Added 'holdResultsOpenOverStatementClose' property (default is false), that keeps result sets open over statement.close() or new execution on same statement (suggested by Kevin Burton). - Fixed BUG#7952 -- Infinite recursion when 'falling back' to master in failover configuration. - Disable multi-statements (if enabled) for MySQL-4.1 versions prior to version 4.1.10 if the query cache is enabled, as the server returns wrong results in this configuration. - Fixed duplicated code in configureClientCharset() that prevented useOldUTF8Behavior=true from working properly. - Removed 'dontUnpackBinaryResults' functionality, the driver now always stores results from server-side prepared statements as-is from the server and unpacks them on demand. - Fixed BUG#8096 where emulated locators corrupt binary data when using server-side prepared statements. - Fixed synchronization issue with ServerPreparedStatement.serverPrepare() that could cause deadlocks/crashes if connection was shared between threads. - By default, the driver now scans SQL you are preparing via all variants of Connection.prepareStatement() to determine if it is a supported type of statement to prepare on the server side, and if it is not supported by the server, it instead prepares it as a client-side emulated prepared statement (BUG#4718). You can disable this by passing 'emulateUnsupportedPstmts=false' in your JDBC URL. - Remove _binary introducer from parameters used as in/out parameters in CallableStatement. - Always return byte[]s for output parameters registered as *BINARY. - Send correct value for 'boolean' "true" to server for PreparedStatement.setObject(n, "true", Types.BIT). - Fixed bug with Connection not caching statements from prepareStatement() when the statement wasn't a server-side prepared statement. - Choose correct 'direction' to apply time adjustments when both client and server are in GMT timezone when using ResultSet.get(..., cal) and PreparedStatement.set(...., cal). - Added 'dontTrackOpenResources' option (default is false, to be JDBC compliant), which helps with memory use for non-well-behaved apps (i.e applications which don't close Statements when they should). - Fixed BUG#8428 - ResultSet.getString() doesn't maintain format stored on server, bug fix only enabled when 'noDatetimeStringSync' property is set to 'true' (the default is 'false'). - Fixed NPE in ResultSet.realClose() when using usage advisor and result set was already closed. - Fixed BUG#8487 - PreparedStatements not creating streaming result sets. - Don't pass NULL to String.valueOf() in ResultSet.getNativeConvertToString(), as it stringifies it (i.e. returns "null"), which is not correct for the method in question. - Fixed BUG#8484 - ResultSet.getBigDecimal() throws exception when rounding would need to occur to set scale. The driver now chooses a rounding mode of 'half up' if non-rounding BigDecimal.setScale() fails. - Added 'useLocalSessionState' configuration property, when set to 'true' the JDBC driver trusts that the application is well-behaved and only sets autocommit and transaction isolation levels using the methods provided on java.sql.Connection, and therefore can manipulate these values in many cases without incurring round-trips to the database server. - Added enableStreamingResults() to Statement for connection pool implementations that check Statement.setFetchSize() for specification-compliant values. Call Statement.setFetchSize(>=0) to disable the streaming results for that statement. - Added support for BIT type in MySQL-5.0.3. The driver will treat BIT(1-8) as the JDBC standard BIT type (which maps to java.lang.Boolean), as the server does not currently send enough information to determine the size of a bitfield when < 9 bits are declared. BIT(>9) will be treated as VARBINARY, and will return byte[] when getObject() is called. 12-23-04 - Version 3.1.6-stable - Fixed hang on SocketInputStream.read() with Statement.setMaxRows() and multiple result sets when driver has to truncate result set directly, rather than tacking a 'LIMIT n' on the end of it. - Fixed BUG#7026 - DBMD.getProcedures() doesn't respect catalog parameter. 12-02-04 - Version 3.1.5-gamma - Fix comparisons made between string constants and dynamic strings that are either toUpperCase()d or toLowerCase()d to use Locale.ENGLISH, as some locales 'override' case rules for English. Also use StringUtils.indexOfIgnoreCase() instead of .toUpperCase().indexOf(), avoids creating a very short-lived transient String instance. - Fixed BUG#5235 - Server-side prepared statements did not honor 'zeroDateTimeBehavior' property, and would cause class-cast exceptions when using ResultSet.getObject(), as the all-zero string was always returned. - Fixed batched updates with server prepared statements weren't looking if the types had changed for a given batched set of parameters compared to the previous set, causing the server to return the error 'Wrong arguments to mysql_stmt_execute()'. - Handle case when string representation of timestamp contains trailing '.' with no numbers following it. - Fixed BUG#5706 - Inefficient detection of pre-existing string instances in ResultSet.getNativeString(). - Don't throw exceptions for Connection.releaseSavepoint(). - Use a per-session Calendar instance by default when decoding dates from ServerPreparedStatements (set to old, less performant behavior by setting property 'dynamicCalendars=true'). - Added experimental configuration property 'dontUnpackBinaryResults', which delays unpacking binary result set values until they're asked for, and only creates object instances for non-numerical values (it is set to 'false' by default). For some usecase/jvm combinations, this is friendlier on the garbage collector. - Fixed BUG#5729 - UNSIGNED BIGINT unpacked incorrectly from server-side prepared statement result sets. - Fixed BUG#6225 - ServerSidePreparedStatement allocating short-lived objects un-necessarily. - Removed un-wanted new Throwable() in ResultSet constructor due to bad merge (caused a new object instance that was never used for every result set created) - Found while profiling for BUG#6359. - Fixed too-early creation of StringBuffer in EscapeProcessor.escapeSQL(), also return String when escaping not needed (to avoid unnecssary object allocations). Found while profiling for BUG#6359. - Use null-safe-equals for key comparisons in updatable result sets. - Fixed BUG#6537, SUM() on Decimal with server-side prepared statement ignores scale if zero-padding is needed (this ends up being due to conversion to DOUBLE by server, which when converted to a string to parse into BigDecimal, loses all 'padding' zeros). - Use DatabaseMetaData.getIdentifierQuoteString() when building DBMD queries. - Use 1MB packet for sending file for LOAD DATA LOCAL INFILE if that is < 'max_allowed_packet' on server. - Fixed BUG#6399, ResultSetMetaData.getColumnDisplaySize() returns incorrect values for multi-byte charsets. - Make auto-deserialization of java.lang.Objects stored in BLOBs configurable via 'autoDeserialize' property (defaults to 'false'). - Re-work Field.isOpaqueBinary() to detect 'CHAR(n) CHARACTER SET BINARY' to support fixed-length binary fields for ResultSet.getObject(). - Use our own implementation of buffered input streams to get around blocking behavior of java.io.BufferedInputStream. Disable this with 'useReadAheadInput=false'. - Fixed BUG#6348, failing to connect to the server when one of the addresses for the given host name is IPV6 (which the server does not yet bind on). The driver now loops through _all_ IP addresses for a given host, and stops on the first one that accepts() a socket.connect(). 09-04-04 - Version 3.1.4-beta - Fixed BUG#4510 - connector/j 3.1.3 beta does not handle integers correctly (caused by changes to support unsigned reads in Buffer.readInt() -> Buffer.readShort()). - Added support in DatabaseMetaData.getTables() and getTableTypes() for VIEWs which are now available in MySQL server version 5.0.x. - Fixed BUG#4642 -- ServerPreparedStatement.execute*() sometimes threw ArrayIndexOutOfBoundsException when unpacking field metadata. - Optimized integer number parsing, enable 'old' slower integer parsing using JDK classes via 'useFastIntParsing=false' property. - Added 'useOnlyServerErrorMessages' property, which causes message text in exceptions generated by the server to only contain the text sent by the server (as opposed to the SQLState's 'standard' description, followed by the server's error message). This property is set to 'true' by default. - Fixed BUG#4689 - ResultSet.wasNull() does not work for primatives if a previous null was returned. - Track packet sequence numbers if enablePacketDebug=true, and throw an exception if packets received out-of-order. - Fixed BUG#4482, ResultSet.getObject() returns wrong type for strings when using prepared statements. - Calling MysqlPooledConnection.close() twice (even though an application error), caused NPE. Fixed. - Fixed BUG#5012 -- ServerPreparedStatements dealing with return of DECIMAL type don't work. - Fixed BUG#5032 -- ResultSet.getObject() doesn't return type Boolean for pseudo-bit types from prepared statements on 4.1.x (shortcut for avoiding extra type conversion when using binary-encoded result sets obscurred test in getObject() for 'pseudo' bit type) - You can now use URLs in 'LOAD DATA LOCAL INFILE' statements, and the driver will use Java's built-in handlers for retreiving the data and sending it to the server. This feature is not enabled by default, you must set the 'allowUrlInLocalInfile' connection property to 'true'. - The driver is more strict about truncation of numerics on ResultSet.get*(), and will throw an SQLException when truncation is detected. You can disable this by setting 'jdbcCompliantTruncation' to false (it is enabled by default, as this functionality is required for JDBC compliance). - Added three ways to deal with all-zero datetimes when reading them from a ResultSet, 'exception' (the default), which throws an SQLException with an SQLState of 'S1009', 'convertToNull', which returns NULL instead of the date, and 'round', which rounds the date to the nearest closest value which is '0001-01-01'. - Fixed ServerPreparedStatement to read prepared statement metadata off the wire, even though it's currently a placeholder instead of using MysqlIO.clearInputStream() which didn't work at various times because data wasn't available to read from the server yet. This fixes sporadic errors users were having with ServerPreparedStatements throwing ArrayIndexOutOfBoundExceptions. - Use com.mysql.jdbc.Message's classloader when loading resource bundle, should fix sporadic issues when the caller's classloader can't locate the resource bundle. 07-07-04 - Version 3.1.3-beta - Mangle output parameter names for CallableStatements so they will not clash with user variable names. - Added support for INOUT parameters in CallableStatements. - Fix for BUG#4119, null bitmask sent for server-side prepared statements was incorrect. - Use SQL Standard SQL states by default, unless 'useSqlStateCodes' property is set to 'false'. - Added packet debuging code (see the 'enablePacketDebug' property documentation). - Added constants for MySQL error numbers (publicly-accessible, see com.mysql.jdbc.MysqlErrorNumbers), and the ability to generate the mappings of vendor error codes to SQLStates that the driver uses (for documentation purposes). - Externalized more messages (on-going effort). - Fix for BUG#4311 - Error in retrieval of mediumint column with prepared statements and binary protocol. - Support new timezone variables in MySQL-4.1.3 when 'useTimezone=true' - Support for unsigned numerics as return types from prepared statements. This also causes a change in ResultSet.getObject() for the 'bigint unsigned' type, which used to return BigDecimal instances, it now returns instances of java.lang.BigInteger. 06-09-04 - Version 3.1.2-alpha - Fixed stored procedure parameter parsing info when size was specified for a parameter (i.e. char(), varchar()). - Enabled callable statement caching via 'cacheCallableStmts' property. - Fixed case when no output parameters specified for a stored procedure caused a bogus query to be issued to retrieve out parameters, leading to a syntax error from the server. - Fixed case when no parameters could cause a NullPointerException in CallableStatement.setOutputParameters(). - Removed wrapping of exceptions in MysqlIO.changeUser(). - Fixed sending of split packets for large queries, enabled nio ability to send large packets as well. - Added .toString() functionality to ServerPreparedStatement, which should help if you're trying to debug a query that is a prepared statement (it shows SQL as the server would process). - Added 'gatherPerformanceMetrics' property, along with properties to control when/where this info gets logged (see docs for more info). - ServerPreparedStatements weren't actually de-allocating server-side resources when .close() was called. - Added 'logSlowQueries' property, along with property 'slowQueriesThresholdMillis' to control when a query should be considered 'slow'. - Correctly map output parameters to position given in prepareCall() vs. order implied during registerOutParameter() - fixes BUG#3146. - Correctly detect initial character set for servers >= 4.1.0 - Cleaned up detection of server properties. - Support placeholder for parameter metadata for server >= 4.1.2 - Fix for BUG#3539 getProcedures() does not return any procedures in result set - Fix for BUG#3540 getProcedureColumns() doesn't work with wildcards for procedure name - Fixed BUG#3520 -- DBMD.getSQLStateType() returns incorrect value. - Added 'connectionCollation' property to cause driver to issue 'set collation_connection=...' query on connection init if default collation for given charset is not appropriate. - Fixed DatabaseMetaData.getProcedures() when run on MySQL-5.0.0 (output of 'show procedure status' changed between 5.0.1 and 5.0.0. - Fixed BUG#3804 -- getWarnings() returns SQLWarning instead of DataTruncation - Don't enable server-side prepared statements for server version 5.0.0 or 5.0.1, as they aren't compatible with the '4.1.2+' style that the driver uses (the driver expects information to come back that isn't there, so it hangs). 02-14-04 - Version 3.1.1-alpha - Fixed bug with UpdatableResultSets not using client-side prepared statements. - Fixed character encoding issues when converting bytes to ASCII when MySQL doesn't provide the character set, and the JVM is set to a multi-byte encoding (usually affecting retrieval of numeric values). - Unpack 'unknown' data types from server prepared statements as Strings. - Implemented long data (Blobs, Clobs, InputStreams, Readers) for server prepared statements. - Implemented Statement.getWarnings() for MySQL-4.1 and newer (using 'SHOW WARNINGS'). - Default result set type changed to TYPE_FORWARD_ONLY (JDBC compliance). - Centralized setting of result set type and concurrency. - Re-factored how connection properties are set and exposed as DriverPropertyInfo as well as Connection and DataSource properties. - Support for NIO. Use 'useNIO=true' on platforms that support NIO. - Support for SAVEPOINTs (MySQL >= 4.0.14 or 4.1.1). - Support for mysql_change_user()...See the changeUser() method in com.mysql.jdbc.Connection. - Reduced number of methods called in average query to be more efficient. - Prepared Statements will be re-prepared on auto-reconnect. Any errors encountered are postponed until first attempt to re-execute the re-prepared statement. - Ensure that warnings are cleared before executing queries on prepared statements, as-per JDBC spec (now that we support warnings). - Support 'old' profileSql capitalization in ConnectionProperties. This property is deprecated, you should use 'profileSQL' if possible. - Optimized Buffer.readLenByteArray() to return shared empty byte array when length is 0. - Allow contents of PreparedStatement.setBlob() to be retained between calls to .execute*(). - Deal with 0-length tokens in EscapeProcessor (caused by callable statement escape syntax). - Check for closed connection on delete/update/insert row operations in UpdatableResultSet. - Fix support for table aliases when checking for all primary keys in UpdatableResultSet. - Removed useFastDates connection property. - Correctly initialize datasource properties from JNDI Refs, including explicitly specified URLs. - DatabaseMetaData now reports supportsStoredProcedures() for MySQL versions >= 5.0.0 - Fixed stack overflow in Connection.prepareCall() (bad merge). - Fixed IllegalAccessError to Calendar.getTimeInMillis() in DateTimeValue (for JDK < 1.4). - Fix for BUG#1673, where DatabaseMetaData.getColumns() is not returning correct column ordinal info for non '%' column name patterns. - Merged fix of datatype mapping from MySQL type 'FLOAT' to java.sql.Types.REAL from 3.0 branch. - Detect collation of column for RSMD.isCaseSensitive(). - Fixed sending of queries > 16M. - Added named and indexed input/output parameter support to CallableStatement. MySQL-5.0.x or newer. - Fixed NullPointerException in ServerPreparedStatement.setTimestamp(), as well as year and month descrepencies in ServerPreparedStatement.setTimestamp(), setDate(). - Added ability to have multiple database/JVM targets for compliance and regression/unit tests in build.xml. - Fixed NPE and year/month bad conversions when accessing some datetime functionality in ServerPreparedStatements and their resultant result sets. - Display where/why a connection was implicitly closed (to aid debugging). - CommunicationsException implemented, that tries to determine why communications was lost with a server, and displays possible reasons when .getMessage() is called. - Fixed BUG#2359, NULL values for numeric types in binary encoded result sets causing NullPointerExceptions. - Implemented Connection.prepareCall(), and DatabaseMetaData. getProcedures() and getProcedureColumns(). - Reset 'long binary' parameters in ServerPreparedStatement when clearParameters() is called, by sending COM_RESET_STMT to the server. - Merged prepared statement caching, and .getMetaData() support from 3.0 branch. - Fixed off-by-1900 error in some cases for years in TimeUtil.fastDate/TimeCreate() when unpacking results from server-side prepared statements. - Fixed BUG#2502 -- charset conversion issue in getTables(). - Implemented multiple result sets returned from a statement or stored procedure. - Fixed BUG#2606 -- Server side prepared statements not returning datatype 'YEAR' correctly. - Enabled streaming of result sets from server-side prepared statements. - Fixed BUG#2623 -- Class-cast exception when using scrolling result sets and server-side prepared statements. - Merged unbuffered input code from 3.0. - Fixed ConnectionProperties that weren't properly exposed via accessors, cleaned up ConnectionProperties code. - Fixed BUG#2671, NULL fields not being encoded correctly in all cases in server side prepared statements. - Fixed rare buffer underflow when writing numbers into buffers for sending prepared statement execution requests. - Use DocBook version of docs for shipped versions of drivers. 02-18-03 - Version 3.1.0-alpha - Added 'requireSSL' property. - Added 'useServerPrepStmts' property (default 'false'). The driver will use server-side prepared statements when the server version supports them (4.1 and newer) when this property is set to 'true'. It is currently set to 'false' by default until all bind/fetch functionality has been implemented. Currently only DML prepared statements are implemented for 4.1 server-side prepared statements. - Track open Statements, close all when Connection.close() is called (JDBC compliance). 06-23-05 - Version 3.0.17-ga - Fixed BUG#5874, Timestamp/Time conversion goes in the wrong 'direction' when useTimeZone='true' and server timezone differs from client timezone. - Fixed BUG#7081, DatabaseMetaData.getIndexInfo() ignoring 'unique' parameter. - Support new protocol type 'MYSQL_TYPE_VARCHAR'. - Added 'useOldUTF8Behavoior' configuration property, which causes JDBC driver to act like it did with MySQL-4.0.x and earlier when the character encoding is 'utf-8' when connected to MySQL-4.1 or newer. - Fixed BUG#7316 - Statements created from a pooled connection were returning physical connection instead of logical connection when getConnection() was called. - Fixed BUG#7033 - PreparedStatements don't encode Big5 (and other multi-byte) character sets correctly in static SQL strings. - Fixed BUG#6966, connections starting up failed-over (due to down master) never retry master. - Fixed BUG#7061, PreparedStatement.fixDecimalExponent() adding extra '+', making number unparseable by MySQL server. - Fixed BUG#7686, Timestamp key column data needed "_binary'" stripped for UpdatableResultSet.refreshRow(). - Backported SQLState codes mapping from Connector/J 3.1, enable with 'useSqlStateCodes=true' as a connection property, it defaults to 'false' in this release, so that we don't break legacy applications (it defaults to 'true' starting with Connector/J 3.1). - Fixed BUG#7601, PreparedStatement.fixDecimalExponent() adding extra '+', making number unparseable by MySQL server. - Escape sequence {fn convert(..., type)} now supports ODBC-style types that are prepended by 'SQL_'. - Fixed duplicated code in configureClientCharset() that prevented useOldUTF8Behavior=true from working properly. - Handle streaming result sets with > 2 billion rows properly by fixing wraparound of row number counter. - Fixed BUG#7607 - MS932, SHIFT_JIS and Windows_31J not recog. as aliases for sjis. - Fixed BUG#6549 (while fixing #7607), adding 'CP943' to aliases for sjis. - Fixed BUG#8064, which requires hex escaping of binary data when using multi-byte charsets with prepared statements. - Fixed BUG#8812, NON_UNIQUE column from DBMD.getIndexInfo() returned inverted value. - Workaround for server BUG#9098 - default values of CURRENT_* for DATE/TIME/TIMESTAMP/TIMESTAMP columns can't be distinguished from 'string' values, so UpdatableResultSet.moveToInsertRow() generates bad SQL for inserting default values. - Fixed BUG#8629 - 'EUCKR' charset is sent as 'SET NAMES euc_kr' which MySQL-4.1 and newer doesn't understand. - DatabaseMetaData.supportsSelectForUpdate() returns correct value based on server version. - Use hex escapes for PreparedStatement.setBytes() for double-byte charsets including 'aliases' Windows-31J, CP934, MS932. - Added support for the "EUC_JP_Solaris" character encoding, which maps to a MySQL encoding of "eucjpms" (backported from 3.1 branch). This only works on servers that support eucjpms, namely 5.0.3 or later. 11-15-04 - Version 3.0.16-ga - Re-issue character set configuration commands when re-using pooled connections and/or Connection.changeUser() when connected to MySQL-4.1 or newer. - Fixed ResultSetMetaData.isReadOnly() to detect non-writable columns when connected to MySQL-4.1 or newer, based on existence of 'original' table and column names. - Fixed BUG#5664, ResultSet.updateByte() when on insert row throws ArrayOutOfBoundsException. - Fixed DatabaseMetaData.getTypes() returning incorrect (i.e. non-negative) scale for the 'NUMERIC' type. - Fixed BUG#6198, off-by-one bug in Buffer.readString(string). - Made TINYINT(1) -> BIT/Boolean conversion configurable via 'tinyInt1isBit' property (default 'true' to be JDBC compliant out of the box). - Only set 'character_set_results' during connection establishment if server version >= 4.1.1. - Fixed regression where useUnbufferedInput was defaulting to 'false'. - Fixed BUG#6231, ResultSet.getTimestamp() on a column with TIME in it fails. 09-04-04 - Version 3.0.15-production - Fixed BUG#4010 - StringUtils.escapeEasternUnicodeByteStream is still broken for GBK - Fixed BUG#4334 - Failover for autoReconnect not using port #'s for any hosts, and not retrying all hosts. (WARN: This required a change to the SocketFactory connect() method signature, which is now public Socket connect(String host, int portNumber, Properties props) therefore any third-party socket factories will have to be changed to support this signature. - Logical connections created by MysqlConnectionPoolDataSource will now issue a rollback() when they are closed and sent back to the pool. If your application server/connection pool already does this for you, you can set the 'rollbackOnPooledClose' property to false to avoid the overhead of an extra rollback(). - Removed redundant calls to checkRowPos() in ResultSet. - Fixed BUG#4742, 'DOUBLE' mapped twice in DBMD.getTypeInfo(). - Added FLOSS license exemption. - Fixed BUG#4808, calling .close() twice on a PooledConnection causes NPE. - Fixed BUG#4138 and BUG#4860, DBMD.getColumns() returns incorrect JDBC type for unsigned columns. This affects type mappings for all numeric types in the RSMD.getColumnType() and RSMD.getColumnTypeNames() methods as well, to ensure that 'like' types from DBMD.getColumns() match up with what RSMD.getColumnType() and getColumnTypeNames() return. - 'Production' - 'GA' in naming scheme of distributions. - Fix for BUG#4880, RSMD.getPrecision() returning 0 for non-numeric types (should return max length in chars for non-binary types, max length in bytes for binary types). This fix also fixes mapping of RSMD.getColumnType() and RSMD.getColumnTypeName() for the BLOB types based on the length sent from the server (the server doesn't distinguish between TINYBLOB, BLOB, MEDIUMBLOB or LONGBLOB at the network protocol level). - Fixed BUG#5022 - ResultSet should release Field[] instance in .close(). - Fixed BUG#5069 -- ResultSet.getMetaData() should not return incorrectly-initialized metadata if the result set has been closed, but should instead throw an SQLException. Also fixed for getRow() and getWarnings() and traversal methods by calling checkClosed() before operating on instance-level fields that are nullified during .close(). - Parse new timezone variables from 4.1.x servers. - Use _binary introducer for PreparedStatement.setBytes() and set*Stream() when connected to MySQL-4.1.x or newer to avoid misinterpretation during character conversion. 05-28-04 - Version 3.0.14-production - Fixed URL parsing error 05-27-04 - Version 3.0.13-production - Fixed BUG#3848 - Using a MySQLDatasource without server name fails - Fixed BUG#3920 - "No Database Selected" when using MysqlConnectionPoolDataSource. - Fixed BUG#3873 - PreparedStatement.getGeneratedKeys() method returns only 1 result for batched insertions 05-18-04 - Version 3.0.12-production - Add unsigned attribute to DatabaseMetaData.getColumns() output in the TYPE_NAME column. - Added 'failOverReadOnly' property, to allow end-user to configure state of connection (read-only/writable) when failed over. - Backported 'change user' and 'reset server state' functionality from 3.1 branch, to allow clients of MysqlConnectionPoolDataSource to reset server state on getConnection() on a pooled connection. - Don't escape SJIS/GBK/BIG5 when using MySQL-4.1 or newer. - Allow 'url' parameter for MysqlDataSource and MysqlConnectionPool DataSource so that passing of other properties is possible from inside appservers. - Map duplicate key and foreign key errors to SQLState of '23000'. - Backport documentation tooling from 3.1 branch. - Return creating statement for ResultSets created by getGeneratedKeys() (BUG#2957) - Allow java.util.Date to be sent in as parameter to PreparedStatement.setObject(), converting it to a Timestamp to maintain full precision (BUG#3103). - Don't truncate BLOBs/CLOBs when using setBytes() and/or setBinary/CharacterStream() (BUG#2670). - Dynamically configure character set mappings for field-level character sets on MySQL-4.1.0 and newer using 'SHOW COLLATION' when connecting. - Map 'binary' character set to 'US-ASCII' to support DATETIME charset recognition for servers >= 4.1.2 - Use 'SET character_set_results" during initialization to allow any charset to be returned to the driver for result sets. - Use charsetnr returned during connect to encode queries before issuing 'SET NAMES' on MySQL >= 4.1.0. - Add helper methods to ResultSetMetaData (getColumnCharacterEncoding() and getColumnCharacterSet()) to allow end-users to see what charset the driver thinks it should be using for the column. - Only set character_set_results for MySQL >= 4.1.0. - Fixed BUG#3511, StringUtils.escapeSJISByteStream() not covering all eastern double-byte charsets correctly. - Renamed StringUtils.escapeSJISByteStream() to more appropriate escapeEasternUnicodeByteStream(). - Fixed BUG#3554 - Not specifying database in URL caused MalformedURL exception. - Auto-convert MySQL encoding names to Java encoding names if used for characterEncoding property. - Added encoding names that are recognized on some JVMs to fix case where they were reverse-mapped to MySQL encoding names incorrectly. - Use junit.textui.TestRunner for all unit tests (to allow them to be run from the command line outside of Ant or Eclipse). - Fixed BUG#3557 - UpdatableResultSet not picking up default values for moveToInsertRow(). - Fixed BUG#3570 - inconsistent reporting of data type. The server still doesn't return all types for *BLOBs *TEXT correctly, so the driver won't return those correctly. - Fixed BUG#3520 -- DBMD.getSQLStateType() returns incorrect value. - Fixed regression in PreparedStatement.setString() and eastern character encodings. - Made StringRegressionTest 4.1-unicode aware. 02-19-04 - Version 3.0.11-stable - Trigger a 'SET NAMES utf8' when encoding is forced to 'utf8' _or_ 'utf-8' via the 'characterEncoding' property. Previously, only the Java-style encoding name of 'utf-8' would trigger this. - AutoReconnect time was growing faster than exponentially (BUG#2447). - Fixed failover always going to last host in list (BUG#2578) - Added 'useUnbufferedInput' parameter, and now use it by default (due to JVM issue http://developer.java.sun.com/developer/bugParade/bugs/4401235.html) - Detect 'on/off' or '1','2','3' form of lower_case_table_names on server. - Return 'java.lang.Integer' for TINYINT and SMALLINT types from ResultSetMetaData.getColumnClassName() (fix for BUG#2852). - Return 'java.lang.Double' for FLOAT type from ResultSetMetaData. getColumnClassName() (fix for BUG#2855). - Return '[B' instead of java.lang.Object for BINARY, VARBINARY and LONGVARBINARY types from ResultSetMetaData.getColumnClassName() (JDBC compliance). - Issue connection events on all instances created from a ConnectionPoolDataSource. 01-13-04 - Version 3.0.10-stable - Don't count quoted id's when inside a 'string' in PreparedStatement parsing (fix for BUG#1511). - 'Friendlier' exception message for PacketTooLargeException (BUG#1534). - Backported fix for aliased tables and UpdatableResultSets in checkUpdatability() method from 3.1 branch. - Fix for ArrayIndexOutOfBounds exception when using Statement.setMaxRows() (BUG#1695). - Fixed BUG#1576, dealing with large blobs and split packets not being read correctly. - Fixed regression of Statement.getGeneratedKeys() and REPLACE statements. - Fixed BUG#1630, subsequent call to ResultSet.updateFoo() causes NPE if result set is not updatable. - Fix for 4.1.1-style auth with no password. - Fix for BUG#1731, Foreign Keys column sequence is not consistent in DatabaseMetaData.getImported/Exported/CrossReference(). - Fix for BUG#1775 - DatabaseMetaData.getSystemFunction() returning bad function 'VResultsSion'. - Fix for BUG#1592 -- cross-database updatable result sets are not checked for updatability correctly. - DatabaseMetaData.getColumns() should return Types.LONGVARCHAR for MySQL LONGTEXT type. - ResultSet.getObject() on TINYINT and SMALLINT columns should return Java type 'Integer' (BUG#1913) - Added 'alwaysClearStream' connection property, which causes the driver to always empty any remaining data on the input stream before each query. - Added more descriptive error message 'Server Configuration Denies Access to DataSource', as well as retrieval of message from server. - Autoreconnect code didn't set catalog upon reconnect if it had been changed. - Implement ResultSet.updateClob(). - ResultSetMetaData.isCaseSensitive() returned wrong value for CHAR/VARCHAR columns. - Fix for BUG#1933 -- Connection property "maxRows" not honored. - Fix for BUG#1925 -- Statements being created too many times in DBMD.extractForeignKeyFromCreateTable(). - Fix for BUG#1914 -- Support escape sequence {fn convert ... } - Fix for BUG#1958 -- ArrayIndexOutOfBounds when parameter number == number of parameters + 1. - Fix for BUG#2006 -- ResultSet.findColumn() should use first matching column name when there are duplicate column names in SELECT query (JDBC-compliance). - Removed static synchronization bottleneck from PreparedStatement.setTimestamp(). - Removed static synchronization bottleneck from instance factory method of SingleByteCharsetConverter. - Enable caching of the parsing stage of prepared statements via the 'cachePrepStmts', 'prepStmtCacheSize' and 'prepStmtCacheSqlLimit' properties (disabled by default). - Speed up parsing of PreparedStatements, try to use one-pass whenever possible. - Fixed security exception when used in Applets (applets can't read the system property 'file.encoding' which is needed for LOAD DATA LOCAL INFILE). - Use constants for SQLStates. - Map charset 'ko18_ru' to 'ko18r' when connected to MySQL-4.1.0 or newer. - Ensure that Buffer.writeString() saves room for the \0. - Fixed exception 'Unknown character set 'danish' on connect w/ JDK-1.4.0 - Fixed mappings in SQLError to report deadlocks with SQLStates of '41000'. - 'maxRows' property would affect internal statements, so check it for all statement creation internal to the driver, and set to 0 when it is not. 10-07-03 - Version 3.0.9-stable - Faster date handling code in ResultSet and PreparedStatement (no longer uses Date methods that synchronize on static calendars). - Fixed test for end of buffer in Buffer.readString(). - Fixed ResultSet.previous() behavior to move current position to before result set when on first row of result set (bugs.mysql.com BUG#496) - Fixed Statement and PreparedStatement issuing bogus queries when setMaxRows() had been used and a LIMIT clause was present in the query. - Fixed BUG#661 - refreshRow didn't work when primary key values contained values that needed to be escaped (they ended up being doubly-escaped). - Support InnoDB contraint names when extracting foreign key info in DatabaseMetaData BUG#517 and BUG#664 (impl. ideas from Parwinder Sekhon) - Backported 4.1 protocol changes from 3.1 branch (server-side SQL states, new field info, larger client capability flags, connect-with-database, and so forth). - Fix UpdatableResultSet to return values for getXXX() when on insert row (BUG#675). - The insertRow in an UpdatableResultSet is now loaded with the default column values when moveToInsertRow() is called (BUG#688) - DatabaseMetaData.getColumns() wasn't returning NULL for default values that are specified as NULL. - Change default statement type/concurrency to TYPE_FORWARD_ONLY and CONCUR_READ_ONLY (spec compliance). - Don't try and reset isolation level on reconnect if MySQL doesn't support them. - Don't wrap SQLExceptions in RowDataDynamic. - Don't change timestamp TZ twice if useTimezone==true (BUG#774) - Fixed regression in large split-packet handling (BUG#848). - Better diagnostic error messages in exceptions for 'streaming' result sets. - Issue exception on ResultSet.getXXX() on empty result set (wasn't caught in some cases). - Don't hide messages from exceptions thrown in I/O layers. - Don't fire connection closed events when closing pooled connections, or on PooledConnection.getConnection() with already open connections (BUG#884). - Clip +/- INF (to smallest and largest representative values for the type in MySQL) and NaN (to 0) for setDouble/setFloat(), and issue a warning on the statement when the server does not support +/- INF or NaN. - Fix for BUG#879, double-escaping of '\' when charset is SJIS or GBK and '\' appears in non-escaped input. - When emptying input stream of unused rows for 'streaming' result sets, have the current thread yield() every 100 rows in order to not monopolize CPU time. - Fixed BUG#1099, DatabaseMetaData.getColumns() getting confused about the keyword 'set' in character columns. - Fixed deadlock issue with Statement.setMaxRows(). - Fixed CLOB.truncate(), BUG#1130 - Optimized CLOB.setChracterStream(), BUG#1131 - Made databaseName, portNumber and serverName optional parameters for MysqlDataSourceFactory (BUG#1246) - Fix for BUG#1247 -- ResultSet.get/setString mashing char 127 - Backported auth. changes for 4.1.1 and newer from 3.1 branch. - Added com.mysql.jdbc.util.BaseBugReport to help creation of testcases for bug reports. - Added property to 'clobber' streaming results, by setting the 'clobberStreamingResults' property to 'true' (the default is 'false'). This will cause a 'streaming' ResultSet to be automatically closed, and any oustanding data still streaming from the server to be discarded if another query is executed before all the data has been read from the server. 05-23-03 - Version 3.0.8-stable - Allow bogus URLs in Driver.getPropertyInfo(). - Return list of generated keys when using multi-value INSERTS with Statement.getGeneratedKeys(). - Use JVM charset with filenames and 'LOAD DATA [LOCAL] INFILE' - Fix infinite loop with Connection.cleanup(). - Changed Ant target 'compile-core' to 'compile-driver', and made testsuite compilation a separate target. - Fixed result set not getting set for Statement.executeUpdate(), which affected getGeneratedKeys() and getUpdateCount() in some cases. - Unicode character 0xFFFF in a string would cause the driver to throw an ArrayOutOfBoundsException (Bug #378) - Return correct amount of generated keys when using 'REPLACE' statements. - Fix problem detecting server character set in some cases. - Fix row data decoding error when using _very_ large packets. - Optimized row data decoding. - Issue exception when operating on an already-closed prepared statement. - Fixed SJIS encoding bug, thanks to Naoto Sato. - Optimized usage of EscapeProcessor. - Allow multiple calls to Statement.close() 04-08-03 - Version 3.0.7-stable - Fixed MysqlPooledConnection.close() calling wrong event type. - Fixed StringIndexOutOfBoundsException in PreparedStatement. setClob(). - 4.1 Column Metadata fixes - Remove synchronization from Driver.connect() and Driver.acceptsUrl(). - IOExceptions during a transaction now cause the Connection to be closed. - Fixed missing conversion for 'YEAR' type in ResultSetMetaData. getColumnTypeName(). - Don't pick up indexes that start with 'pri' as primary keys for DBMD.getPrimaryKeys(). - Throw SQLExceptions when trying to do operations on a forcefully closed Connection (i.e. when a communication link failure occurs). - You can now toggle profiling on/off using Connection.setProfileSql(boolean). - Fixed charset issues with database metadata (charset was not getting set correctly). - Updatable ResultSets can now be created for aliased tables/columns when connected to MySQL-4.1 or newer. - Fixed 'LOAD DATA LOCAL INFILE' bug when file > max_allowed_packet. - Fixed escaping of 0x5c ('\') character for GBK and Big5 charsets. - Fixed ResultSet.getTimestamp() when underlying field is of type DATE. - Ensure that packet size from alignPacketSize() does not exceed MAX_ALLOWED_PACKET (JVM bug) - Don't reset Connection.isReadOnly() when autoReconnecting. 02-18-03 - Version 3.0.6-stable - Fixed ResultSetMetaData to return "" when catalog not known. Fixes NullPointerExceptions with Sun's CachedRowSet. - Fixed DBMD.getTypeInfo() and DBMD.getColumns() returning different value for precision in TEXT/BLOB types. - Allow ignoring of warning for 'non transactional tables' during rollback (compliance/usability) by setting 'ignoreNonTxTables' property to 'true'. - Fixed SQLExceptions getting swallowed on initial connect. - Fixed Statement.setMaxRows() to stop sending 'LIMIT' type queries when not needed (performance) - Clean up Statement query/method mismatch tests (i.e. INSERT not allowed with .executeQuery()). - More checks added in ResultSet traversal method to catch when in closed state. - Fixed ResultSetMetaData.isWritable() to return correct value. - Add 'window' of different NULL sorting behavior to DBMD.nullsAreSortedAtStart (4.0.2 to 4.0.10, true, otherwise, no). - Implemented Blob.setBytes(). You still need to pass the resultant Blob back into an updatable ResultSet or PreparedStatement to persist the changes, as MySQL does not support 'locators'. - Backported 4.1 charset field info changes from Connector/J 3.1 01-22-03 - Version 3.0.5-gamma - Fixed Buffer.fastSkipLenString() causing ArrayIndexOutOfBounds exceptions with some queries when unpacking fields. - Implemented an empty TypeMap for Connection.getTypeMap() so that some third-party apps work with MySQL (IBM WebSphere 5.0 Connection pool). - Added missing LONGTEXT type to DBMD.getColumns(). - Retrieve TX_ISOLATION from database for Connection.getTransactionIsolation() when the MySQL version supports it, instead of an instance variable. - Quote table names in DatabaseMetaData.getColumns(), getPrimaryKeys(), getIndexInfo(), getBestRowIdentifier() - Greatly reduce memory required for setBinaryStream() in PreparedStatements. - Fixed ResultSet.isBeforeFirst() for empty result sets. - Added update options for foreign key metadata. 01-06-03 - Version 3.0.4-gamma - Added quoted identifiers to database names for Connection.setCatalog. - Added support for quoted identifiers in PreparedStatement parser. - Streamlined character conversion and byte[] handling in PreparedStatements for setByte(). - Reduce memory footprint of PreparedStatements by sharing outbound packet with MysqlIO. - Added 'strictUpdates' property to allow control of amount of checking for 'correctness' of updatable result sets. Set this to 'false' if you want faster updatable result sets and you know that you create them from SELECTs on tables with primary keys and that you have selected all primary keys in your query. - Added support for 4.0.8-style large packets. - Fixed PreparedStatement.executeBatch() parameter overwriting. 12-17-02 - Version 3.0.3-dev - Changed charsToByte in SingleByteCharConverter to be non-static - Changed SingleByteCharConverter to use lazy initialization of each converter. - Fixed charset handling in Fields.java - Implemented Connection.nativeSQL() - More robust escape tokenizer -- recognize '--' comments, and allow nested escape sequences (see testsuite.EscapeProcessingTest) - DBMD.getImported/ExportedKeys() now handles multiple foreign keys per table. - Fixed ResultSetMetaData.getPrecision() returning incorrect values for some floating point types. - Fixed ResultSetMetaData.getColumnTypeName() returning BLOB for TEXT and TEXT for BLOB types. - Fixed Buffer.isLastDataPacket() for 4.1 and newer servers. - Added CLIENT_LONG_FLAG to be able to get more column flags (isAutoIncrement() being the most important) - Because of above, implemented ResultSetMetaData.isAutoIncrement() to use Field.isAutoIncrement(). - Honor 'lower_case_table_names' when enabled in the server when doing table name comparisons in DatabaseMetaData methods. - Some MySQL-4.1 protocol support (extended field info from selects) - Use non-aliased table/column names and database names to fullly qualify tables and columns in UpdatableResultSet (requires MySQL-4.1 or newer) - Allow user to alter behavior of Statement/ PreparedStatement.executeBatch() via 'continueBatchOnError' property (defaults to 'true'). - Check for connection closed in more Connection methods (createStatement, prepareStatement, setTransactionIsolation, setAutoCommit). - More robust implementation of updatable result sets. Checks that _all_ primary keys of the table have been selected. - 'LOAD DATA LOCAL INFILE ...' now works, if your server is configured to allow it. Can be turned off with the 'allowLoadLocalInfile' property (see the README). - Substitute '?' for unknown character conversions in single-byte character sets instead of '\0'. - NamedPipeSocketFactory now works (only intended for Windows), see README for instructions. 11-08-02 - Version 3.0.2-dev - Fixed issue with updatable result sets and PreparedStatements not working - Fixed ResultSet.setFetchDirection(FETCH_UNKNOWN) - Fixed issue when calling Statement.setFetchSize() when using arbitrary values - Fixed incorrect conversion in ResultSet.getLong() - Implemented ResultSet.updateBlob(). - Removed duplicate code from UpdatableResultSet (it can be inherited from ResultSet, the extra code for each method to handle updatability I thought might someday be necessary has not been needed). - Fixed "UnsupportedEncodingException" thrown when "forcing" a character encoding via properties. - Fixed various non-ASCII character encoding issues. - Added driver property 'useHostsInPrivileges'. Defaults to true. Affects whether or not '@hostname' will be used in DBMD.getColumn/TablePrivileges. - All DBMD result set columns describing schemas now return NULL to be more compliant with the behavior of other JDBC drivers for other database systems (MySQL does not support schemas). - Added SSL support. See README for information on how to use it. - Properly restore connection properties when autoReconnecting or failing-over, including autoCommit state, and isolation level. - Use 'SHOW CREATE TABLE' when possible for determining foreign key information for DatabaseMetaData...also allows cascade options for DELETE information to be returned - Escape 0x5c character in strings for the SJIS charset. - Fixed start position off-by-1 error in Clob.getSubString() - Implemented Clob.truncate() - Implemented Clob.setString() - Implemented Clob.setAsciiStream() - Implemented Clob.setCharacterStream() - Added com.mysql.jdbc.MiniAdmin class, which allows you to send 'shutdown' command to MySQL server...Intended to be used when 'embedding' Java and MySQL server together in an end-user application. - Added 'connectTimeout' parameter that allows users of JDK-1.4 and newer to specify a maxium time to wait to establish a connection. - Failover and autoReconnect only work when the connection is in a autoCommit(false) state, in order to stay transaction safe - Added 'queriesBeforeRetryMaster' property that specifies how many queries to issue when failed over before attempting to reconnect to the master (defaults to 50) - Fixed DBMD.supportsResultSetConcurrency() so that it returns true for ResultSet.TYPE_SCROLL_INSENSITIVE and ResultSet.CONCUR_READ_ONLY or ResultSet.CONCUR_UPDATABLE - Fixed ResultSet.isLast() for empty result sets (should return false). - PreparedStatement now honors stream lengths in setBinary/Ascii/Character Stream() unless you set the connection property 'useStreamLengthsInPrepStmts' to 'false'. - Removed some not-needed temporary object creation by using Strings smarter in EscapeProcessor, Connection and DatabaseMetaData classes. 09-21-02 - Version 3.0.1-dev - Fixed ResultSet.getRow() off-by-one bug. - Fixed RowDataStatic.getAt() off-by-one bug. - Added limited Clob functionality (ResultSet.getClob(), PreparedStatemtent.setClob(), PreparedStatement.setObject(Clob). - Added socketTimeout parameter to URL. - Connection.isClosed() no longer "pings" the server. - Connection.close() issues rollback() when getAutoCommit() == false - Added "paranoid" parameter...sanitizes error messages removing "sensitive" information from them (such as hostnames, ports, or usernames), as well as clearing "sensitive" data structures when possible. - Fixed ResultSetMetaData.isSigned() for TINYINT and BIGINT. - Charsets now automatically detected. Optimized code for single-byte character set conversion. - Implemented ResultSet.getCharacterStream() - Added "LOCAL TEMPORARY" to table types in DatabaseMetaData.getTableTypes() - Massive code clean-up to follow Java coding conventions (the time had come) 07-31-02 - Version 3.0.0-dev - !!! LICENSE CHANGE !!! The driver is now GPL. If you need non-GPL licenses, please contact me <[email protected]> - JDBC-3.0 functionality including Statement/PreparedStatement.getGeneratedKeys() and ResultSet.getURL() - Performance enchancements - driver is now 50-100% faster in most situations, and creates fewer temporary objects - Repackaging...new driver name is "com.mysql.jdbc.Driver", old name still works, though (the driver is now provided by MySQL-AB) - Better checking for closed connections in Statement and PreparedStatement. - Support for streaming (row-by-row) result sets (see README) Thanks to Doron. - Support for large packets (new addition to MySQL-4.0 protocol), see README for more information. - JDBC Compliance -- Passes all tests besides stored procedure tests - Fix and sort primary key names in DBMetaData (SF bugs 582086 and 582086) - Float types now reported as java.sql.Types.FLOAT (SF bug 579573) - ResultSet.getTimestamp() now works for DATE types (SF bug 559134) - ResultSet.getDate/Time/Timestamp now recognizes all forms of invalid values that have been set to all zeroes by MySQL (SF bug 586058) - Testsuite now uses Junit (which you can get from www.junit.org) - The driver now only works with JDK-1.2 or newer. - Added multi-host failover support (see README) - General source-code cleanup. - Overall speed improvements via controlling transient object creation in MysqlIO class when reading packets - Performance improvements in string handling and field metadata creation (lazily instantiated) contributed by Alex Twisleton-Wykeham-Fiennes 05-16-02 - Version 2.0.14 - More code cleanup - PreparedStatement now releases resources on .close() (SF bug 553268) - Quoted identifiers not used if server version does not support them. Also, if server started with --ansi or --sql-mode=ANSI_QUOTES then '"' will be used as an identifier quote, otherwise '`' will be used. - ResultSet.getDouble() now uses code built into JDK to be more precise (but slower) - LogicalHandle.isClosed() calls through to physical connection - Added SQL profiling (to STDERR). Set "profileSql=true" in your JDBC url. See README for more information. - Fixed typo for relaxAutoCommit parameter. 04-24-02 - Version 2.0.13 - More code cleanup. - Fixed unicode chars being read incorrectly (SF bug 541088) - Faster blob escaping for PrepStmt - Added set/getPortNumber() to DataSource(s) (SF bug 548167) - Added setURL() to MySQLXADataSource (SF bug 546019) - PreparedStatement.toString() fixed (SF bug 534026) - ResultSetMetaData.getColumnClassName() now implemented - Rudimentary version of Statement.getGeneratedKeys() from JDBC-3.0 now implemented (you need to be using JDK-1.4 for this to work, I believe) - DBMetaData.getIndexInfo() - bad PAGES fixed (SF BUG 542201) 04-07-02 - Version 2.0.12 - General code cleanup. - Added getIdleFor() method to Connection and MysqlLogicalHandle. - Relaxed synchronization in all classes, should fix 520615 and 520393. - Added getTable/ColumnPrivileges() to DBMD (fixes 484502). - Added new types to getTypeInfo(), fixed existing types thanks to Al Davis and Kid Kalanon. - Added support for BIT types (51870) to PreparedStatement. - Fixed getRow() bug (527165) in ResultSet - Fixes for ResultSet updatability in PreparedStatement. - Fixed timezone off by 1-hour bug in PreparedStatement (538286, 528785). - ResultSet: Fixed updatability (values being set to null if not updated). - DataSources - fixed setUrl bug (511614, 525565), wrong datasource class name (532816, 528767) - Added identifier quoting to all DatabaseMetaData methods that need them (should fix 518108) - Added support for YEAR type (533556) - ResultSet.insertRow() should now detect auto_increment fields in most cases and use that value in the new row. This detection will not work in multi-valued keys, however, due to the fact that the MySQL protocol does not return this information. - ResultSet.refreshRow() implemented. - Fixed testsuite.Traversal afterLast() bug, thanks to Igor Lastric. 01-27-02 - Version 2.0.11 - Fixed missing DELETE_RULE value in DBMD.getImported/ExportedKeys() and getCrossReference(). - Full synchronization of Statement.java. - More changes to fix "Unexpected end of input stream" errors when reading BLOBs. This should be the last fix. 01-24-02 - Version 2.0.10 - Fixed spurious "Unexpected end of input stream" errors in MysqlIO (bug 507456). - Fixed null-pointer-exceptions when using MysqlConnectionPoolDataSource with Websphere 4 (bug 505839). 01-13-02 - Version 2.0.9 - Ant build was corrupting included jar files, fixed (bug 487669). - Fixed extra memory allocation in MysqlIO.readPacket() (bug 488663). - Implementation of DatabaseMetaData.getExported/ImportedKeys() and getCrossReference(). - Full synchronization on methods modifying instance and class-shared references, driver should be entirely thread-safe now (please let me know if you have problems) - DataSource implementations moved to org.gjt.mm.mysql.jdbc2.optional package, and (initial) implementations of PooledConnectionDataSource and XADataSource are in place (thanks to Todd Wolff for the implementation and testing of PooledConnectionDataSource with IBM WebSphere 4). - Added detection of network connection being closed when reading packets (thanks to Todd Lizambri). - Fixed quoting error with escape processor (bug 486265). - Report batch update support through DatabaseMetaData (bug 495101). - Fixed off-by-one-hour error in PreparedStatement.setTimestamp() (bug 491577). - Removed concatenation support from driver (the '||' operator), as older versions of VisualAge seem to be the only thing that use it, and it conflicts with the logical '||' operator. You will need to start mysqld with the "--ansi" flag to use the '||' operator as concatenation (bug 491680) - Fixed casting bug in PreparedStatement (bug 488663). 11-25-01 - Version 2.0.8 - Batch updates now supported (thanks to some inspiration from Daniel Rall). - XADataSource/ConnectionPoolDataSource code (experimental) - PreparedStatement.setAnyNumericType() now handles positive exponents correctly (adds "+" so MySQL can understand it). - DatabaseMetaData.getPrimaryKeys() and getBestRowIdentifier() are now more robust in identifying primary keys (matches regardless of case or abbreviation/full spelling of Primary Key in Key_type column). 10-24-01 - Version 2.0.7 - PreparedStatement.setCharacterStream() now implemented - Fixed dangling socket problem when in high availability (autoReconnect=true) mode, and finalizer for Connection will close any dangling sockets on GC. - Fixed ResultSetMetaData.getPrecision() returning one less than actual on newer versions of MySQL. - ResultSet.getBlob() now returns null if column value was null. - Character sets read from database if useUnicode=true and characterEncoding is not set. (thanks to Dmitry Vereshchagin) - Initial transaction isolation level read from database (if avaialable) (thanks to Dmitry Vereshchagin) - Fixed DatabaseMetaData.supportsTransactions(), and supportsTransactionIsolationLevel() and getTypeInfo() SQL_DATETIME_SUB and SQL_DATA_TYPE fields not being readable. - Fixed PreparedStatement generating SQL that would end up with syntax errors for some queries. - Fixed ResultSet.isAfterLast() always returning false. - Fixed timezone issue in PreparedStatement.setTimestamp() (thanks to Erik Olofsson) - Captialize type names when "captializeTypeNames=true" is passed in URL or properties (for WebObjects, thanks to Anjo Krank) - Updatable result sets now correctly handle NULL values in fields. - PreparedStatement.setDouble() now uses full-precision doubles (reverting a fix made earlier to truncate them). - PreparedStatement.setBoolean() will use 1/0 for values if your MySQL version is 3.21.23 or higher. 06-16-01 - Version 2.0.6 - Fixed PreparedStatement parameter checking - Fixed case-sensitive column names in ResultSet.java 06-13-01 - Version 2.0.5 - Fixed ResultSet.getBlob() ArrayIndex out-of-bounds - Fixed ResultSetMetaData.getColumnTypeName for TEXT/BLOB - Fixed ArrayIndexOutOfBounds when sending large BLOB queries (Max size packet was not being set) - Added ISOLATION level support to Connection.setIsolationLevel() - Fixed NPE on PreparedStatement.executeUpdate() when all columns have not been set. - Fixed data parsing of TIMESTAMPs with 2-digit years - Added Byte to PreparedStatement.setObject() - ResultSet.getBoolean() now recognizes '-1' as 'true' - ResultSet has +/-Inf/inf support - ResultSet.insertRow() works now, even if not all columns are set (they will be set to "NULL") - DataBaseMetaData.getCrossReference() no longer ArrayIndexOOB - getObject() on ResultSet correctly does TINYINT->Byte and SMALLINT->Short 12-03-00 - Version 2.0.3 - Implemented getBigDecimal() without scale component for JDBC2. - Fixed composite key problem with updatable result sets. - Added detection of -/+INF for doubles. - Faster ASCII string operations. - Fixed incorrect detection of MAX_ALLOWED_PACKET, so sending large blobs should work now. - Fixed off-by-one error in java.sql.Blob implementation code. - Added "ultraDevHack" URL parameter, set to "true" to allow (broken) Macromedia UltraDev to use the driver. 04-06-00 - Version 2.0.1 - Fixed RSMD.isWritable() returning wrong value. Thanks to Moritz Maass. - Cleaned up exception handling when driver connects - Columns that are of type TEXT now return as Strings when you use getObject() - DatabaseMetaData.getPrimaryKeys() now works correctly wrt to key_seq. Thanks to Brian Slesinsky. - No escape processing is done on PreparedStatements anymore per JDBC spec. - Fixed many JDBC-2.0 traversal, positioning bugs, especially wrt to empty result sets. Thanks to Ron Smits, Nick Brook, Cessar Garcia and Carlos Martinez. - Fixed some issues with updatability support in ResultSet when using multiple primary keys. 02-21-00 - Version 2.0pre5 - Fixed Bad Handshake problem. 01-10-00 - Version 2.0pre4 - Fixes to ResultSet for insertRow() - Thanks to Cesar Garcia - Fix to Driver to recognize JDBC-2.0 by loading a JDBC-2.0 class, instead of relying on JDK version numbers. Thanks to John Baker. - Fixed ResultSet to return correct row numbers - Statement.getUpdateCount() now returns rows matched, instead of rows actually updated, which is more SQL-92 like. 10-29-99 - Statement/PreparedStatement.getMoreResults() bug fixed. Thanks to Noel J. Bergman. - Added Short as a type to PreparedStatement.setObject(). Thanks to Jeff Crowder - Driver now automagically configures maximum/preferred packet sizes by querying server. - Autoreconnect code uses fast ping command if server supports it. - Fixed various bugs wrt. to packet sizing when reading from the server and when alloc'ing to write to the server. 08-17-99 - Version 2.0pre - Now compiles under JDK-1.2. The driver supports both JDK-1.1 and JDK-1.2 at the same time through a core set of classes. The driver will load the appropriate interface classes at runtime by figuring out which JVM version you are using. - Fixes for result sets with all nulls in the first row. (Pointed out by Tim Endres) - Fixes to column numbers in SQLExceptions in ResultSet (Thanks to Blas Rodriguez Somoza) - The database no longer needs to specified to connect. (Thanks to Christian Motschke) 07-04-99 - Version 1.2b - Better Documentation (in progress), in doc/mm.doc/book1.html - DBMD now allows null for a column name pattern (not in spec), which it changes to '%'. - DBMD now has correct types/lengths for getXXX(). - ResultSet.getDate(), getTime(), and getTimestamp() fixes. (contributed by Alan Wilken) - EscapeProcessor now handles \{ \} and { or } inside quotes correctly. (thanks to Alik for some ideas on how to fix it) - Fixes to properties handling in Connection. (contributed by Juho Tikkala) - ResultSet.getObject() now returns null for NULL columns in the table, rather than bombing out. (thanks to Ben Grosman) - ResultSet.getObject() now returns Strings for types from MySQL that it doesn't know about. (Suggested by Chris Perdue) - Removed DataInput/Output streams, not needed, 1/2 number of method calls per IO operation. - Use default character encoding if one is not specified. This is a work-around for broken JVMs, because according to spec, EVERY JVM must support "ISO8859_1", but they don't. - Fixed Connection to use the platform character encoding instead of "ISO8859_1" if one isn't explicitly set. This fixes problems people were having loading the character- converter classes that didn't always exist (JVM bug). (thanks to Fritz Elfert for pointing out this problem) - Changed MysqlIO to re-use packets where possible to reduce memory usage. - Fixed escape-processor bugs pertaining to {} inside quotes. 04-14-99 - Version 1.2a - Fixed character-set support for non-Javasoft JVMs (thanks to many people for pointing it out) - Fixed ResultSet.getBoolean() to recognize 'y' & 'n' as well as '1' & '0' as boolean flags. (thanks to Tim Pizey) - Fixed ResultSet.getTimestamp() to give better performance. (thanks to Richard Swift) - Fixed getByte() for numeric types. (thanks to Ray Bellis) - Fixed DatabaseMetaData.getTypeInfo() for DATE type. (thanks to Paul Johnston) - Fixed EscapeProcessor for "fn" calls. (thanks to Piyush Shah at locomotive.org) - Fixed EscapeProcessor to not do extraneous work if there are no escape codes. (thanks to Ryan Gustafson) - Fixed Driver to parse URLs of the form "jdbc:mysql://host:port" (thanks to Richard Lobb) 03-24-99 - Version 1.1i - Fixed Timestamps for PreparedStatements - Fixed null pointer exceptions in RSMD and RS - Re-compiled with jikes for valid class files (thanks ms!) 03-08-99 - Version 1.1h - Fixed escape processor to deal with un-matched { and } (thanks to Craig Coles) - Fixed escape processor to create more portable (between DATETIME and TIMESTAMP types) representations so that it will work with BETWEEN clauses. (thanks to Craig Longman) - MysqlIO.quit() now closes the socket connection. Before, after many failed connections some OS's would run out of file descriptors. (thanks to Michael Brinkman) - Fixed NullPointerException in Driver.getPropertyInfo. (thanks to Dave Potts) - Fixes to MysqlDefs to allow all *text fields to be retrieved as Strings. (thanks to Chris at Leverage) - Fixed setDouble in PreparedStatement for large numbers to avoid sending scientific notation to the database. (thanks to J.S. Ferguson) - Fixed getScale() and getPrecision() in RSMD. (contrib'd by James Klicman) - Fixed getObject() when field was DECIMAL or NUMERIC (thanks to Bert Hobbs) - DBMD.getTables() bombed when passed a null table-name pattern. Fixed. (thanks to Richard Lobb) - Added check for "client not authorized" errors during connect. (thanks to Hannes Wallnoefer) 02-19-99 - Version 1.1g - Result set rows are now byte arrays. Blobs and Unicode work bidriectonally now. The useUnicode and encoding options are implemented now. - Fixes to PreparedStatement to send binary set by setXXXStream to be sent un-touched to the MySQL server. - Fixes to getDriverPropertyInfo(). 12-31-98 - Version 1.1f - Changed all ResultSet fields to Strings, this should allow Unicode to work, but your JVM must be able to convert between the character sets. This should also make reading data from the server be a bit quicker, because there is now no conversion from StringBuffer to String. - Changed PreparedStatement.streamToString() to be more efficient (code from Uwe Schaefer). - URL parsing is more robust (throws SQL exceptions on errors rather than NullPointerExceptions) - PreparedStatement now can convert Strings to Time/Date values via setObject() (code from Robert Currey). - IO no longer hangs in Buffer.readInt(), that bug was introduced in 1.1d when changing to all byte-arrays for result sets. (Pointed out by Samo Login) 11-03-98 - Version 1.1b - Fixes to DatabaseMetaData to allow both IBM VA and J-Builder to work. Let me know how it goes. (thanks to Jac Kersing) - Fix to ResultSet.getBoolean() for NULL strings (thanks to Barry Lagerweij) - Beginning of code cleanup, and formatting. Getting ready to branch this off to a parallel JDBC-2.0 source tree. - Added "final" modifier to critical sections in MysqlIO and Buffer to allow compiler to inline methods for speed. 9-29-98 - If object references passed to setXXX() in PreparedStatement are null, setNull() is automatically called for you. (Thanks for the suggestion goes to Erik Ostrom) - setObject() in PreparedStatement will now attempt to write a serialized representation of the object to the database for objects of Types.OTHER and objects of unknown type. - Util now has a static method readObject() which given a ResultSet and a column index will re-instantiate an object serialized in the above manner. 9-02-98 - Vesion 1.1 - Got rid of "ugly hack" in MysqlIO.nextRow(). Rather than catch an exception, Buffer.isLastDataPacket() was fixed. - Connection.getCatalog() and Connection.setCatalog() should work now. - Statement.setMaxRows() works, as well as setting by property maxRows. Statement.setMaxRows() overrides maxRows set via properties or url parameters. - Automatic re-connection is available. Because it has to "ping" the database before each query, it is turned off by default. To use it, pass in "autoReconnect=true" in the connection URL. You may also change the number of reconnect tries, and the initial timeout value via "maxReconnects=n" (default 3) and "initialTimeout=n" (seconds, default 2) parameters. The timeout is an exponential backoff type of timeout, e.g. if you have initial timeout of 2 seconds, and maxReconnects of 3, then the driver will timeout 2 seconds, 4 seconds, then 16 seconds between each re-connection attempt. 8-24-98 - Version 1.0 - Fixed handling of blob data in Buffer.java - Fixed bug with authentication packet being sized too small. - The JDBC Driver is now under the LPGL 8-14-98 - - Fixed Buffer.readLenString() to correctly read data for BLOBS. - Fixed PreparedStatement.stringToStream to correctly read data for BLOBS. - Fixed PreparedStatement.setDate() to not add a day. (above fixes thanks to Vincent Partington) - Added URL parameter parsing (?user=... and so forth). 8-04-98 - Version 0.9d - Big news! New package name. Tim Endres from ICE Engineering is starting a new source tree for GNU GPL'd Java software. He's graciously given me the org.gjt.mm package directory to use, so now the driver is in the org.gjt.mm.mysql package scheme. I'm "legal" now. Look for more information on Tim's project soon. - Now using dynamically sized packets to reduce memory usage when sending commands to the DB. - Small fixes to getTypeInfo() for parameters, and so forth. - DatabaseMetaData is now fully implemented. Let me know if these drivers work with the various IDEs out there. I've heard that they're working with JBuilder right now. - Added JavaDoc documentation to the package. - Package now available in .zip or .tar.gz. 7-28-98 - Version 0.9 - Implemented getTypeInfo(). Connection.rollback() now throws an SQLException per the JDBC spec. - Added PreparedStatement that supports all JDBC API methods for PreparedStatement including InputStreams. Please check this out and let me know if anything is broken. - Fixed a bug in ResultSet that would break some queries that only returned 1 row. - Fixed bugs in DatabaseMetaData.getTables(), DatabaseMetaData.getColumns() and DatabaseMetaData.getCatalogs(). - Added functionality to Statement that allows executeUpdate() to store values for IDs that are automatically generated for AUTO_INCREMENT fields. Basically, after an executeUpdate(), look at the SQLWarnings for warnings like "LAST_INSERTED_ID = 'some number', COMMAND = 'your SQL query'". If you are using AUTO_INCREMENT fields in your tables and are executing a lot of executeUpdate()s on one Statement, be sure to clearWarnings() every so often to save memory. 7-06-98 - Version 0.8 - Split MysqlIO and Buffer to separate classes. Some ClassLoaders gave an IllegalAccess error for some fields in those two classes. Now mm.mysql works in applets and all classloaders. Thanks to Joe Ennis <[email protected]> for pointing out the problem and working on a fix with me. 7-01-98 - Version 0.7 - Fixed DatabaseMetadata problems in getColumns() and bug in switch statement in the Field constructor. Thanks to Costin Manolache <[email protected]> for pointing these out. 5-21-98 - Version 0.6 - Incorporated efficiency changes from Richard Swift <[email protected]> in MysqlIO.java and ResultSet.java - We're now 15% faster than gwe's driver. - Started working on DatabaseMetaData. The following methods are implemented: * getTables() * getTableTypes() * getColumns * getCatalogs()
MySQL Connector/MXJ is a Java Utility package for deploying and managing a MySQL database. Connector/MXJ may be bundled in to an existing Java application or may be deployed as a JMX MBean. Deploying and using MySQL can be as easy as adding an additional parameter to the JDBC connection url, which will result in the database being started when the first connection is made. This makes it easy for Java developers to deploy applications which require a database by reducing installation barriers for their end-users.
MySQL Connector/MXJ makes the MySQL database appear to be a java-based component. It does this by determining what platform the system is running on, selecting the appropriate binary, and launching the executable. It will also optionally deploy an initial database, with any specified parameters.
As a JMX MBean, MySQL Connector/MXJ requires a JMX v1.2 compliant MBean container, such as JBoss version 4. The MBean will uses the standard JMX management APIs to present (and allow the setting of) parameters which are appropriate for that platform.
Included are instructions for use with a JDBC driver and deploying as a JMX MBean to JBoss.
You can download sources and binaries from: http://dev.mysql.com/downloads/connector/mxj/
This a beta release and feedback is welcome and encouraged.
Please send questions or comments to [email protected].
Linux, i386
Windows NT, x86
Windows 2000, x86
Windows XP, x86
Solaris 9, SPARC 32
The best way to ensure that your platform is supported is to run the JUnit tests.
The first thing to do is make sure that the components will work
on the platform. The MysqldResource
class
is really a wrapper for a native version of MySQL, so not all
platforms are supported. At the time of this writing, Linux on the
i386 architecture has been tested and seems to work quite well, as
does OS X v10.3. There has been limited testing on Windows and
Solaris.
Requirements:
JDK-1.4 or newer (or the JRE if you aren't going to be compiling the source or JSPs).
MySQL Connector/J version 3.1 or newer (from http://dev.mysql.com/downloads/connector/j/ ) installed and available via your CLASSPATH.
The javax.management
classes for JMX
version 1.2.1, these are present in the following application
servers:
JBoss - 4.0rc1 or newer
Apache Tomcat - 5.0 or newer
Sun's JMX reference implementation version 1.2.1 http://java.sun.com/products/JavaManagement/
Junit 3.8.1 (from http://www.junit.org/)
If building from source, All of the requirements from above, plus:
Ant version 1.5 or newer (download from http://ant.apache.org/)
The tests attempt to launch MySQL on the port 3336. If you have a MySQL running, it may conflict, but this isn't very likely because the default port for MySQL is 3306. However, You may set the "c-mxj_test_port" Java property to a port of your choosing. Alternatively, you may wish to start by shutting down any instances of MySQL you have running on the target machine.
The tests surpress output to the console by default. For verbose output, you may set the "c-mxj_test_silent" Java property to "false".
In order to run the JUnit test suite, the $CLASSPATH must include the following:
JUnit
JMX
Connector/J
MySQL Connector/MXJ
If connector-mxj.jar
is not present in
your download, unzip MySQL Connector/MXJ source archive.
cd mysqldjmx ant dist
Then add
$TEMP/cmxj/stage/connector-mxj/connector-mxj.jar
to the CLASSPATH.
if you have junit
, execute the unit tests.
From the command line, type:
java junit.textui.TestRunner com.mysql.management.AllTestsSuite
The output should look something like this:
......................................... ......................................... .......... Time: 259.438 OK (101 tests)
Note that the tests are a bit slow near the end, so please be patient.
A feature of the MySQL Connector/J JDBC driver is the ability to specify a ''SocketFactory'' as a parameter in the JDBC connection string. MySQL Connector/MXJ includes a custom SocketFactory. The SocketFactory will, upon the first connection, deploy and launch the MySQL database. The SocketFactory also exposes a ''shutdown'' method.
To try it specify the ''socketFactory'' parameter on the JDBC connection string with a value equal to ''com.mysql.management.driverlaunched.ServerLauncherSocketFactory''
In the following example, we have a program which creates a connection, executes a query, and prints the result to the System.out. The MySQL database will be deployed and started as part of the connection process, and shutdown as part of the finally block.
import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; import com.mysql.management.driverlaunched.ServerLauncherSocketFactory; public class ConnectorMXJTestExample { public static void main(String[] args) throws Exception { String hostColonPort = "localhost:3336"; String driver = com.mysql.jdbc.Driver.class.getName(); String url = "jdbc:mysql://" + hostColonPort + "/" + "?" + "socketFactory=" + ServerLauncherSocketFactory.class.getName(); String userName = "root"; String password = ""; Class.forName(driver); Connection conn = null; try { conn = DriverManager.getConnection(url, userName, password); Statement stmt = conn.createStatement(); ResultSet rs = stmt.executeQuery("SELECT VERSION()"); rs.next(); String version = rs.getString(1); rs.close(); stmt.close(); System.out.println("------------------------"); System.out.println(version); System.out.println("------------------------"); } finally { try { conn.close(); } catch (Exception e) { e.printStackTrace(); } ServerLauncherSocketFactory.shutdown(hostColonPort); } } }
To run the above program, be sure to have connector-mxj.jar and Connector/J in the CLASSPATH. Then type:
java ConnectorMXJTestExample
Of course there are many options we may wish to set for a MySQL database. These options may be specified as part of the JDBC connection string simply by prefixing each server option with ''server.''. In the following example we set three driver parameters and two server parameters:
String url = "jdbc:mysql://" + hostColonPort + "/" + "?" + "socketFactory=" + ServerLauncherSocketFactory.class.getName(); + "&" + "cacheServerConfiguration=true" + "&" + "useLocalSessionState=true" + "&" + "server.basedir=/opt/myapp/db" + "&" + "server.datadir=/mnt/bigdisk/myapp/data";
Have a java application and wish to "embed" a MySQL database, make use of the com.mysql.management.MysqldResource class directly. This class may be instantiated with the default (no argument) constructor, or by passing in a java.io.File object representing the directory you wish the server to be "unzipped" into. It may also be instantiated with printstreams for "stdout" and "stderr" for logging.
Once instantiated, a java.util.Map, the object will be able to provide a java.util.Map of server options appropriate for the platform and version of MySQL which you will be using.
The MysqldResource will allow you to "start" MySQL with a java.util.Map of server options which you provide, as well as "shutdown" the database. The following example shows a simplistic way to embed MySQL in an application using plain java objects:
import com.mysql.management.MysqldResource; ... public void startMySQL() { File baseDir = new File(ourAppDir, "mysql"); mysqldResource = new MysqldResource(baseDir); Map options = new HashMap(); options.put("port", "3336"); String threadName = "OurApp MySQL"; mysqldResource.start(threadName, options); } public void stopMySQL() { if (mysqldResource != null) { mysqldResource.shutdown(); } mysqldResource = null; } public java.sql.Connection getConnection() throws Exception { String db = "test"; String url = "jdbc:mysql://localhost:3336/" + db; String userName = "root"; String password = ""; Class.forName(com.mysql.jdbc.Driver.class.getName()); return DriverManager.getConnection(url, userName, password); }
Constructors:
public MysqldResource(File baseDir, PrintStream out, PrintStream err);
Allows the setting of the "basedir" to deploy the MySQL files to, as well as out put streams for standard out and standard err.
public MysqldResource(File baseDir);
Allows the setting of the "basedir" to deploy the MySQL files to. Output for standard out and standard err are directed to System.out and System.err.
public MysqldResource();
The basedir is defaulted to a subdirectory of the java.io.tempdir. Output for standard out and standard err are directed to System.out and System.err;
MysqldResource API includes the following methods:
void start(String threadName, Map mysqldArgs);
Deploys and starts MySQL. The "threadName" string is used to name the thread which actually performs the execution of the MySQL command line. The map is the set of arguments and their values to be passed to the command line.
void shutdown();
Shuts down the MySQL instance managed by the MysqldResource object.
Map getServerOptions();
Returns a map of all the options and their current (or default, if not running) options available for the MySQL database.
boolean isRunning();
Returns true if the MySQL database is running.
boolean isReadyForConnections();
Returns true once the database reports that is ready for connections.
void setKillDelay(int millis);
The default "Kill Delay" is 30 seconds. This represents the amount of time to wait between the initial request to shutdown and issuing a "force kill" if the database has not shutdown by itself.
void addCompletionListenser(Runnable listener);
Allows for applications to be notified when the server process completes. Each ''listener'' will be fired off in its own thread.
String getVersion();
returns the version of MySQL.
void setVersion(int MajorVersion, int minorVersion, int patchLevel);
The standard distribution comes with only one version of MySQL packaged. However, it is possible to package multiple versions, and specify which version to use.
If you are not using the SUN Reference implementation of the JMX libraries, you should skip this section. Or, if you are deploying to JBoss, you also may wish to skip to the next section.
We want to see the MysqldDynamicMBean in action inside of a JMX
agent. In the com.mysql.management.jmx.sunri
package is a custom JMX agent with two MBeans:
the MysqldDynamicMBean, and
a com.sun.jdmk.comm.HtmlAdaptorServer, which provides a web interface for manipulating the beans inside of a JMX agent.
When this very simple agent is started, it will allow a MySQL database to be started and stopped with a web browser.
Complete the testing of the platform as above.
current JDK, JUnit, Connector/J, MySQL Connector/MXJ
this section requires the SUN reference implementation of JMX
PATH, JAVA_HOME, ANT_HOME, CLASSPATH
If not building from source, skip to next step
rebuild with the "sunri.present"
ant -Dsunri.present=true dist re-run tests: java junit.textui.TestRunner com.mysql.management.AllTestsSuite
launch the test agent from the command line:
java com.mysql.management.jmx.sunri.MysqldTestAgentSunHtmlAdaptor &
from a browser:
http://localhost:9092/
under MysqldAgent,
select "name=mysqld"
Observe the MBean View
scroll to the bottom of the screen press the
button
click Back to MBean View
scroll to the bottom of the screen press
buttonkill the java process running the Test Agent (jmx server)
Once there is confidence that the MBean will function on the platform, deploying the MBean inside of a standard JMX Agent is the next step. Included are instructions for deploying to JBoss.
Ensure a current version of java development kit (v1.4.x), see above.
Ensure JAVA_HOME
is set (JBoss requires
JAVA_HOME
)
Ensure JAVA_HOME/bin
is in the
PATH
(You will NOT need to set your
CLASSPATH, nor will you need any of the jars used in the
previous tests).
Ensure a current version of JBoss (v4.0RC1 or better)
http://www.jboss.org/index.html select "Downloads" select "jboss-4.0.zip" pick a mirror unzip ~/dload/jboss-4.0.zip create a JBOSS_HOME environment variable set to the unzipped directory unix only: cd $JBOSS_HOME/bin chmod +x *.sh
Deploy (copy) the connector-mxj.jar
to
$JBOSS_HOME/server/default/lib
.
Deploy (copy)
mysql-connector-java-3.1.4-beta-bin.jar
to $JBOSS_HOME/server/default/lib
.
Create a mxjtest.war
directory in
$JBOSS_HOME/server/default/deploy
.
Deploy (copy) index.jsp
to
$JBOSS_HOME/server/default/deploy/mxjtest.war
.
Create a mysqld-service.xml
file in
$JBOSS_HOME/server/default/deploy
.
<?xml version="1.0" encoding="UTF-8"?> <server> <mbean code="com.mysql.management.jmx.jboss.JBossMysqldDynamicMBean" name="mysql:type=service,name=mysqld"> <attribute name="datadir">/tmp/xxx_data_xxx</attribute> <attribute name="autostart">true</attribute> </mbean> </server>
Start jboss:
on unix: $JBOSS_HOME/bin/run.sh
on windows: %JBOSS_HOME%\bin\run.bat
Be ready: JBoss sends a lot of output to the screen.
When JBoss seems to have stopped sending output to the screen,
open a web browser to:
http://localhost:8080/jmx-console
Scroll down to the bottom of the page in the
mysql
section, select the bulleted
mysqld
link.
Observe the JMX MBean View page. MySQL should already be running.
(If "autostart=true" was set, you may skip this step.) Scroll
to the bottom of the screen. You may press the
Operation completed successfully without a
return value.
Click Back to MBean
View
To confirm MySQL is running, open a web browser to
http://localhost:8080/mxjtest/
and you
should see that
SELECT 1
returned with a result of
1
Guided by the
$JBOSS_HOME/server/default/deploy/mxjtest.war/index.jsp
you will be able to use MySQL in your Web Application. There
is a test
database and a
root
user (no password) ready to expirement
with. Try creating a table, inserting some rows, and doing
some selects.
Shut down MySQL. MySQL will be stopped automatically when
JBoss is stopped, or: from the browser, scroll down to the
bottom of the MBean View press the stop service
Operation completed successfully without a
return value.
Using ps
or
task manager
see that MySQL is no longer
running
As of 1.0.6-beta version is the ability to have the MBean start the MySQL database upon start up. Also, we've taken advantage of the JBoss life-cycle extension methods so that the database will gracefully shut down when JBoss is shutdown.
If you've worked through the above sections, you've arleady performed these steps. But we list them here for quick reference.
Driver Launched:
Download and unzip Connector/MXJ, add connector-mxj.jar to the CLASSPATH
To the JDBC connection string add the following parameter: "socketFactory=" + ServerLauncherSocketFactory.class.getName()
JBoss:
Download Connector/MXJ copy the
connector-mxj.jar
file to the
$JBOSS_HOME/server/default/lib
diretory.
Download Connector/J copy the
connector-mxj.jar
file to the
$JBOSS_HOME/server/default/lib
diretory.
Create an MBean service xml file in the
$JBOSS_HOME/server/default/deploy
directory with any attributes set, for instance the
datadir
and autostart
.
Set the JDBC parameters of your web application to use:
String driver = "com.mysql.jdbc.Driver"; String url
= "jdbc:mysql:///test?propertiesTransform="+
"com.mysql.management.jmx.ConnectorMXJPropertiesTransform";
String user = "root"; String password = "";
Class.forName(driver); Connection conn =
DriverManager.getConnection(url, user, password);
You may wish to create a separate users and database table spaces for each application, rather than using "root and test".
We highly suggest having a routine backup procedure for backing up
the database files in the datadir
.