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https://dev.mysql.com/doc/refman/8.4/en/optimizing-myisam.html
The MyISAM storage engine performs best with read-mostly data or with low-concurrency operations, because table locks limit the ability to perform simultaneous updates. In MySQL, InnoDB is the default storage engine rather than MyISAM.
https://dev.mysql.com/doc/refman/8.4/en/permission-optimization.html
The more complex your privilege setup, the more overhead applies to all SQL statements. Simplifying the privileges established by GRANT statements enables MySQL to reduce permission-checking overhead when clients execute statements. For example, if ...
https://dev.mysql.com/doc/refman/8.4/en/statement-optimization.html
The core logic of a database application is performed through SQL statements, whether issued directly through an interpreter or submitted behind the scenes through an API. The tuning guidelines in this section help to speed up all kinds of MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/bnl-bka-optimization.html
The block_nested_loop flag of the optimizer_switch system variable controls hash joins. The batched_key_access flag controls how the optimizer uses the Batched Key Access join algorithms. Optimizer hints may also be applied; see Optimizer Hints for ... In MySQL, a Batched Key Access (BKA) Join algorithm is available that uses both index access to the joined table and a join ...
https://dev.mysql.com/doc/internals/en/optimizer-joins-access-methods.html
Bad join choices can cause more damage than bad choices in single-table searches, so MySQL developers have spent proportionally more time making sure that the tables in a query are joined in an optimal order and that optimal access methods (often ...A combination of a fixed order in which tables are joined and the corresponding table access methods for each table is called query execution plan ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-persistent-stats.html
The persistent optimizer statistics feature improves plan stability by storing statistics to disk and making them persistent across server restarts so that the optimizer is more likely to make consistent choices each time for a given query.
https://dev.mysql.com/doc/refman/8.4/en/innodb-parameters.html
For general I/O tuning advice, see Section 10.5.8, “Optimizing InnoDB Disk I/O”. For general I/O tuning advice, see Section 10.5.8, “Optimizing InnoDB Disk I/O”. innodb_change_buffering Command-Line Format --innodb-change-buffering=value ...
https://dev.mysql.com/doc/refman/8.4/en/glossary.html
The adaptive flushing algorithm extends this process by estimating the optimal rate to perform these periodic flushes, based on the rate of flushing and how fast redo information is generated. adaptive hash index An optimization for InnoDB tables ...
https://dev.mysql.com/doc/refman/8.4/en/cost-model.html
To generate execution plans, the optimizer uses a cost model that is based on estimates of the cost of various operations that occur during query execution. The optimizer has a set of compiled-in default “cost constants” available to it to make ...These estimates are stored in the server_cost and engine_cost tables in the mysql system database and are configurable at any ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-statistics-estimation.html
Optimizer statistics are not persisted to disk when innodb_stats_persistent=OFF or when individual tables are created or altered with STATS_PERSISTENT=0. Optimizer statistics are persisted to disk by default, enabled by the innodb_stats_persistent ...Instead, statistics are stored in memory, and are lost when the server is shut ...