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https://dev.mysql.com/doc/workbench/en/wb-performance-explain.html
The visual explain feature generates and displays a visual representation of the MySQL EXPLAIN statement by using extended information available in the extended JSON format. For information about how MySQL executes statements, see Optimizing ...
https://dev.mysql.com/doc/refman/8.4/en/create-table-generated-columns.html
A stored column does require storage space and can be indexed. Other attributes may be given to indicate whether the column is indexed or can be NULL, or provide a comment. If expression evaluation causes truncation or provides incorrect input to a ...Values of a generated column are computed from an expression included in the column ...
https://dev.mysql.com/doc/refman/8.4/en/date-and-time-functions.html
The return type of this function and of the SUBTIME() function is determined as follows: If the first argument is a dynamic parameter (such as in a prepared statement), the return type is TIME. If the first argument is a dynamic parameter (for ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-repair.html
Note that when you do mysqladmin shutdown on a remote server, the mysqld server is still available for a while after mysqladmin returns, until all statement-processing has stopped and all index changes have been flushed to disk. You can also use the ... The discussion in this section describes how to use myisamchk on MyISAM tables (extensions .MYI and ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-autocommit-commit-rollback.html
If autocommit mode is enabled, each SQL statement forms a single transaction on its own. By default, MySQL starts the session for each new connection with autocommit enabled, so MySQL does a commit after each SQL statement if that statement did not ...If autocommit mode is disabled within a session with SET autocommit = 0, the session always has a transaction ...
https://dev.mysql.com/doc/ndbapi/en/ndb-error-codes-schema-error.html
The following list enumerates all NDB errors of type SE (Schema error).
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-queries.html
To tune queries for InnoDB tables, create an appropriate set of indexes on each table. Follow these guidelines for InnoDB indexes: Because each InnoDB table has a primary key (whether you request one or not), specify a set of primary key columns ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-table-wait-summary-tables.html
The following sections describe the table I/O and lock wait summary tables: table_io_waits_summary_by_index_usage: Table I/O waits per index table_io_waits_summary_by_table: Table I/O waits per table table_lock_waits_summary_by_table: Table lock ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-replication-schema.html
The SELECT statement used to find the closest binary log position to the highest applied epoch on the replica in a multi-source setup (see Section 25.7.10, “NDB Cluster Replication: Bidirectional and Circular Replication”) employs these two ...
https://dev.mysql.com/doc/refman/8.4/en/archive-storage-engine.html
The ARCHIVE storage engine produces special-purpose tables that store large amounts of unindexed data in a very small footprint. You can check whether the ARCHIVE storage engine is available with the SHOW ENGINES statement. The AUTO_INCREMENT ...To ...