7.6.5.1 Installing or Uninstalling ddl_rewriter

This section describes how to install or uninstall the ddl_rewriter plugin. For general information about installing plugins, see Section 7.6.1, “Installing and Uninstalling Plugins”.

Note

If installed, the ddl_rewriter plugin involves some minimal overhead even when disabled. To avoid this overhead, install ddl_rewriter only for the period during which you intend to use it.

The primary use case is modification of statements restored from dump files, so the typical usage pattern is: 1) Install the plugin; 2) restore the dump file or files; 3) uninstall the plugin.

To be usable by the server, the plugin library file must be located in the MySQL plugin directory (the directory named by the plugin_dir system variable). If necessary, configure the plugin directory location by setting the value of plugin_dir at server startup.

The plugin library file base name is ddl_rewriter. The file name suffix differs per platform (for example, .so for Unix and Unix-like systems, .dll for Windows).

To install the ddl_rewriter plugin, use the INSTALL PLUGIN statement, adjusting the .so suffix for your platform as necessary:

INSTALL PLUGIN ddl_rewriter SONAME 'ddl_rewriter.so';

To verify plugin installation, examine the Information Schema PLUGINS table or use the SHOW PLUGINS statement (see Section 7.6.2, “Obtaining Server Plugin Information”). For example:

mysql> SELECT PLUGIN_NAME, PLUGIN_STATUS, PLUGIN_TYPE
       FROM INFORMATION_SCHEMA.PLUGINS
       WHERE PLUGIN_NAME LIKE 'ddl%';
+--------------+---------------+-------------+
| PLUGIN_NAME  | PLUGIN_STATUS | PLUGIN_TYPE |
+--------------+---------------+-------------+
| ddl_rewriter | ACTIVE        | AUDIT       |
+--------------+---------------+-------------+

As the preceding result shows, ddl_rewriter is implemented as an audit plugin.

If the plugin fails to initialize, check the server error log for diagnostic messages.

Once installed as just described, ddl_rewriter remains installed until uninstalled. To remove it, use UNINSTALL PLUGIN:

UNINSTALL PLUGIN ddl_rewriter;

If ddl_rewriter is installed, you can use the --ddl-rewriter option for subsequent server startups to control ddl_rewriter plugin activation. For example, to prevent the plugin from being enabled at runtime, use this option:

[mysqld]
ddl-rewriter=OFF