4.1.2 The mysqld-max Extended MySQL Server - MySQL
If you need to administer MySQL, this article gets you off to a good start. The first of a multi-part series, it is excerpted from chapter four of the book MySQL Administrator's Guide, written by Paul Dubois (Sams; ISBN: 0672326345).
A MySQL-Max server is a version of the mysqld MySQL server that has been built to include additional features.
The 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 you need not get a special distribution. Just use a regular Windows distribution, available at http://dev.mysql.com/downloads/mysql-4.0.html. See Section 2.2.1, "Installing MySQL on Windows."
For Linux, if you install MySQL using RPM distributions, use the regular MySQL-server RPM first to install a standard server named mysqld. Then use the MySQL-Max RPM to install a server named mysqld-max. The MySQL-Max RPM presupposes that you have already installed the regular server RPM. See Section 2.2.2, "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.
MySQL AB builds the MySQL-Max servers by using the following configure options:
This option adds a -max suffix to the mysqld version string.
This option enables support for the InnoDB storage engine. MySQL-Max servers always include InnoDB support, but this option actually is needed only for MySQL 3.23. From MySQL 4 on, InnoDB is included by default in binary distributions, so you do not need a MySQL-Max server to obtain InnoDB support.
This option enables support for the Berkeley DB (BDB) storage engine.
This define enables symbolic link support for Windows.
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. The following table shows which platforms allow MySQL-Max binaries to include BDB:
Mac OS X
To find out which storage engines your server supports, issue the following statement:
mysql> SHOW ENGINES;
Before MySQL 4.1.2, SHOW ENGINES is unavailable. Use the following statement instead and check the value of the variable for the storage engine in which you are interested:
mysql> SHOW VARIABLES LIKE 'have_%';
| Variable_name | Value |
| have_bdb | NO |
| have_crypt | YES |
| have_innodb | YES |
| have_isam | NO |
| have_raid | NO |
| have_symlink | DISABLED |
| have_openssl | NO |
| have_query_cache | YES |
The values in the second column indicate the server's level of support for each feature:
The feature is supported and is active.
The feature is not supported.
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 host_name.err error log file should contain a reason indicating why the option is disabled.
One situation in which you might see DISABLED occurs with MySQL 3.23 when the InnoDB storage engine is compiled in. In MySQL 3.23, you must supply at least the innodb_data_file_path option at runtime to set up the InnoDB tablespace. Without this option, InnoDB disables itself. See Section 9.3, "InnoDB in MySQL 3.23." You can specify configuration options for the BDB storage engine, too, but BDB will not disable itself if you do not provide them. See Section 8.4.3, "BDB Startup Options."
You might also see DISABLED for the InnoDB, BDB, or ISAM storage engines if the server was compiled to support them, but was started with the --skip-innodb, --skip-bdb, or --skip-isam options at runtime.
As of Version 3.23, all MySQL servers support MyISAM tables, because MyISAM is the default storage engine.