Rechercher dans le manuel MySQL

15.12.5 Online DDL Failure Conditions

Contents

The failure of an online DDL operation is typically due to one of the following conditions:

  • An ALGORITHM clause specifies an algorithm that is not compatible with the particular type of DDL operation or storage engine.

  • A LOCK clause specifies a low degree of locking (SHARED or NONE) that is not compatible with the particular type of DDL operation.

  • A timeout occurs while waiting for an exclusive lock on the table, which may be needed briefly during the initial and final phases of the DDL operation.

  • The tmpdir or innodb_tmpdir file system runs out of disk space, while MySQL writes temporary sort files on disk during index creation. For more information, see Section 15.12.3, “Online DDL Space Requirements”.

  • The operation takes a long time and concurrent DML modifies the table so much that the size of the temporary online log exceeds the value of the innodb_online_alter_log_max_size configuration option. This condition causes a DB_ONLINE_LOG_TOO_BIG error.

  • Concurrent DML makes changes to the table that are allowed with the original table definition, but not with the new one. The operation only fails at the very end, when MySQL tries to apply all the changes from concurrent DML statements. For example, you might insert duplicate values into a column while a unique index is being created, or you might insert NULL values into a column while creating a primary key index on that column. The changes made by the concurrent DML take precedence, and the ALTER TABLE operation is effectively rolled back.


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-innodb-online-ddl-failure-conditions.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

  1. View the html document Language of the document:en 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