4.3. The mysqld-max Extended MySQL Server

A MySQL-Max server is a version of the mysqld MySQL server that has been built to include additional features. The MySQL-Max distribution to use depends on your platform:

• For Windows, MySQL binary distributions include both the standard server (mysqld.exe) and the MySQL-Max server (mysqld-max.exe), so no special distribution is needed. Just use a regular Windows distribution. See Section 2.3, "Installing MySQL on Windows."

• For Linux, if you install MySQL using RPM distributions, the MySQL-Max RPM presupposes that you have already installed the regular server RPM. Use the regular MySQL-server RPM first to install a standard server named mysqld, and then use the MySQL-Max RPM to install a server named mysqld-max. See Section 2.4, "Installing MySQL on Linux," for more information on the Linux RPM packages.

• All other MySQL-Max distributions contain a single server that is named mysqld but that has the additional features included.

You can find the MySQL-Max binaries on the MySQL AB Web site at http://dev.mysql.com/downloads/.

MySQL AB builds the MySQL-Max servers by using the following configure options:

• --with-server-suffix=-max

  This option adds a -max suffix to the mysqld version string.

• --with-innodb

  This option enables support for the InnoDB storage engine. MySQL-Max servers always include InnoDB support. From MySQL 4.0 onward, InnoDB is included by default in all binary distributions, so a MySQL-Max server is not needed to obtain InnoDB support.

• --with-bdb

  This option enables support for the Berkeley DB (BDB) storage engine on those platforms for which BDB is available. (See notes in the following discussion.)

• --with-blackhole-storage-engine

  This option enables support for the BLACKHOLE storage engine.

• --with-csv-storage-engine

  This option enables support for the CSV storage engine.

• --with-example-storage-engine

  This option enables support for the EXAMPLE storage engine.

• --with-federated-storage-engine

  This option enables support for the FEDERATED storage engine.

• --with-ndbcluster

  This option enables support for the NDB Cluster storage engine on those platforms for which Cluster is available. (See notes in the following discussion.)

• USE_SYMDIR

  This define is enabled to turn on database symbolic link support for Windows. From MySQL 4.0 onward, symbolic link support is enabled for all Windows servers, so a MySQL-Max server is not needed to take advantage of this feature.

MySQL-Max binary distributions are a convenience for those who wish to install precompiled programs. If you build MySQL using a source distribution, you can build your own Max-like server by enabling the same features at configuration time that the MySQL-Max binary distributions are built with.

MySQL-Max servers include the BerkeleyDB (BDB) storage engine whenever possible, but not all platforms support BDB.

Currently, MySQL Cluster is supported on Linux (on most platforms), Solaris, Mac OS X, and HP-UX only. Some users have reported success in using MySQL Cluster built from source on BSD operating systems, but these are not officially supported at this time. Note that, even for servers compiled with Cluster support, the NDB Cluster storage engine is not enabled by default. You must start the server with the --ndbcluster option to use it as part of a MySQL Cluster. (For details, see Section 9.4, "MySQL Cluster Configuration.")

The following table shows the platforms for which MySQL-Max binaries include support for BDB and NDB Cluster.

System	BDB Support	NDB Support
AIX 5.2	N	N
HP-UX	Y	Y
Linux-IA-64	N	Y
Linux-Intel	Y	Y
Mac OS X	N	Y
NetWare	N	N
SCO 6	N	N
Solaris-SPARC	Y	Y
Solaris-Intel	N	Y
Solaris-AMD 64	Y	Y
Windows NT/2000/XP	Y	N

To find out which storage engines your server supports, use the SHOW ENGINES statement. For example:

mysql> SHOW ENGINES\G
*************************** 1. row ***************************
  Engine: MyISAM
Support: DEFAULT
Comment: Default engine as of MySQL 3.23 with great performance
*************************** 2. row ***************************
  Engine: MEMORY
Support: YES
Comment: Hash based, stored in memory, useful for temporary tables
*************************** 3. row ***************************
  Engine: InnoDB
Support: YES
Comment: Supports transactions, row-level locking, and foreign keys
*************************** 4. row ***************************
  Engine: BerkeleyDB
Support: NO
Comment: Supports transactions and page-level locking
*************************** 5. row ***************************
  Engine: BLACKHOLE
Support: YES
Comment: /dev/null storage engine (anything you write to it disappears)
...

The precise output from SHOW ENGINES may vary according to the MySQL version used (and the features that are enabled). The Support values in the output indicate the server's level of support for each feature, as shown here:

Value	Meaning
YES	The feature is supported and is active.
NO	The feature is not supported.
DISABLED	The feature is supported but has been disabled.

A value of NO means that the server was compiled without support for the feature, so it cannot be activated at runtime.

A value of DISABLED occurs either because the server was started with an option that disables the feature, or because not all options required to enable it were given. In the latter case, the error log file should contain a reason indicating why the option is disabled. See Section 4.12.1, "The Error Log."

You might also see DISABLED for a storage engine if the server was compiled to support it, but was started with a --skip-engine option. For example, --skip-innodb disables the InnoDB engine. For the NDB Cluster storage engine, DISABLED means the server was compiled with support for MySQL Cluster, but was not started with the --ndb-cluster option.

All MySQL servers support MyISAM tables, because MyISAM is the default storage engine.