5.6.4 The Rewriter Query Rewrite Plugin

MySQL supports query rewrite plugins that can examine and possibly modify SQL statements received by the server before the server executes them. See Query Rewrite Plugins.

MySQL distributions include a postparse query rewrite plugin named Rewriter and scripts for installing the plugin and its associated components. These components work together to provide statement-rewriting capability:

A server-side plugin named Rewriter examines statements and may rewrite them, based on its in-memory cache of rewrite rules.
These statements are subject to rewriting:
- As of MySQL 8.0.12: SELECT, INSERT, REPLACE, UPDATE, and DELETE.
- Prior to MySQL 8.0.12: SELECT only.
Standalone statements and prepared statements are subject to rewriting. Statements occurring within view definitions or stored programs are not subject to rewriting.
The Rewriter plugin uses a database named query_rewrite containing a table named rewrite_rules. The table provides persistent storage for the rules that the plugin uses to decide whether to rewrite statements. Users communicate with the plugin by modifying the set of rules stored in this table. The plugin communicates with users by setting the message column of table rows.
The query_rewrite database contains a stored procedure named flush_rewrite_rules() that loads the contents of the rules table into the plugin.
A user-defined function named load_rewrite_rules() is used by the flush_rewrite_rules() stored procedure.
The Rewriter plugin exposes system variables that enable plugin configuration and status variables that provide runtime operational information.

The following sections describe how to install and use the Rewriter plugin, and provide reference information for its associated components.

Find a PHP function

Document created the 26/06/2006, last modified the 26/10/2018
Source of the printed document:https://www.gaudry.be/en/mysql-rf-rewriter-query-rewrite-plugin.html

The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.

References

Manuel MySQL : https://dev.mysql.com/

These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.

Contents Haut