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https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-limitations.html
OPTIMIZE TABLE for an InnoDB table is mapped to an ALTER TABLE operation to rebuild the table and update index statistics and free unused space in the clustered index. OPTIMIZE TABLE is supported with the addition of online DDL support for ... The ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-read_ahead.html
For more information about I/O performance, see Section 10.5.8, “Optimizing InnoDB Disk I/O” and Section 10.12.1, “Optimizing Disk I/O”. A read-ahead request is an I/O request to prefetch multiple pages in the buffer pool asynchronously, in ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-temporary-tablespace.html
Session Temporary Tablespaces Session temporary tablespaces store user-created temporary tables and internal temporary tables created by the optimizer when InnoDB is configured as the storage engine for on-disk internal temporary tables. A maximum ... InnoDB uses session temporary tablespaces and a global temporary ...
https://dev.mysql.com/doc/refman/8.4/en/kill.html
Warning Killing a REPAIR TABLE or OPTIMIZE TABLE operation on a MyISAM table results in a table that is corrupted and unusable. Any reads or writes to such a table fail until you optimize or repair it again (without interruption). KILL [CONNECTION ...
https://dev.mysql.com/doc/refman/8.4/en/load-data.html
For information about the efficiency of INSERT versus LOAD DATA and speeding up LOAD DATA, see Section 10.2.5.1, “Optimizing INSERT Statements”. The file can be read from the server host or the client host, depending on whether the LOCAL ...
https://dev.mysql.com/doc/refman/8.4/en/memory-use.html
The storage engine interface enables the optimizer to provide information about the size of the record buffer to be used for scans that the optimizer estimates are likely to read multiple rows. MySQL allocates buffers and caches to improve ...
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-other-options.html
This improves join performance by enabling the join optimizer to better choose the order in which to join the tables and which indexes it should use. This optimizes seeks and makes table scans that use indexes faster. myisamchk supports the ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-online-add-node-basics.html
You can do this by issuing, for each NDBCLUSTER table, an OPTIMIZE TABLE statement in the mysql client. OPTIMIZE TABLE is not supported for fixed-width columns of in-memory tables; it is also not supported for Disk Data tables. In this section, we ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-online-add-node-example.html
In addition, for each table, the ALTER TABLE statement should be followed by an OPTIMIZE TABLE to reclaim wasted space. REORGANIZE PARTITION and OPTIMIZE TABLE statements for each existing NDBCLUSTER table. In this section we provide a detailed ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-commands.html
If there is a concern that optimizer-hint comments may be stored in object definitions so that dump files when reloaded with mysql would result in execution of such commands, either invoke mysql with the --binary-mode option or use a reload client ... mysql sends each SQL statement that you issue to the server to be ...