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https://dev.mysql.com/doc/refman/8.4/en/internal-temporary-tables.html
In some cases, the server creates internal temporary tables while processing statements. The server creates temporary tables under conditions such as these: Evaluation of UNION statements, with some exceptions described later. Evaluation of some ...
https://dev.mysql.com/doc/refman/8.4/en/locale-support.html
The locale indicated by the lc_time_names system variable controls the language used to display day and month names and abbreviations. This variable affects the output from the DATE_FORMAT(), DAYNAME(), and MONTHNAME() functions. The lc_time_names ...
https://dev.mysql.com/doc/refman/8.4/en/metadata-locking.html
MySQL uses metadata locking to manage concurrent access to database objects and to ensure data consistency. Metadata locking applies not just to tables, but also to schemas, stored programs (procedures, functions, triggers, scheduled events), ...
https://dev.mysql.com/doc/refman/8.4/en/monitor-mysql-memory-use.html
The following example demonstrates how to use Performance Schema and sys schema to monitor MySQL memory usage. Instruments can be enabled by updating the ENABLED column of the Performance Schema setup_instruments table. Memory instruments have ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-logs-cluster-log.html
The following table lists the most common NDB cluster log messages. For information about the cluster log, log events, and event types, see Section 25.6.3, “Event Reports Generated in NDB Cluster”. These log messages also correspond to log ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-replication-auto-sync.html
It is possible to automate much of the process described in the previous section (see Section 25.7.9, “NDB Cluster Backups With NDB Cluster Replication”). The following Perl script reset-replica.pl serves as an example of how you can do this.
https://dev.mysql.com/doc/refman/8.4/en/mysql-nutshell.html
This section summarizes what has been added to, deprecated in, changed, and removed from MySQL 8.4 since MySQL 8.0. A companion section lists MySQL server options and variables that have been added, deprecated, or removed in MySQL 8.4; see Section ...
https://dev.mysql.com/doc/refman/8.4/en/no-login-pluggable-authentication.html
The mysql_no_login server-side authentication plugin prevents all client connections to any account that uses it. Use cases for this plugin include: Accounts that must be able to execute stored programs and views with elevated privileges without ...
https://dev.mysql.com/doc/refman/8.4/en/optimizer-statistics.html
The column_statistics data dictionary table stores histogram statistics about column values, for use by the optimizer in constructing query execution plans. The column_statistics table has these characteristics: The table contains statistics for ...
https://dev.mysql.com/doc/refman/8.4/en/outer-join-optimization.html
MySQL implements an A LEFT JOIN B join_specification as follows: Table B is set to depend on table A and all tables on which A depends. Table A is set to depend on all tables (except B) that are used in the LEFT JOIN condition. The LEFT JOIN ...