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https://dev.mysql.com/doc/internals/en/implementing-the-info-method.html
The optimizer requests an update of table information by calling the [custom-engine.html#custom-engine-api-reference-info handler::info()] method. If you cannot provide an accurate number quickly you should set the value to be greater than 1 so ...
https://dev.mysql.com/doc/refman/8.4/en/aggregate-functions.html
SELECT COUNT(*) FROM tbl_name query performance for InnoDB tables is optimized for single-threaded workloads if there are no extra clauses such as WHERE or GROUP BY. InnoDB processes SELECT COUNT(*) statements by traversing the smallest available ...
https://dev.mysql.com/doc/refman/8.4/en/create-table.html
This helps the MySQL optimizer to prioritize which index to use and also more quickly to detect duplicated UNIQUE keys. Table Options Table options are used to optimize the behavior of the table. For more information about the persistent statistics ...| {FULLTEXT | SPATIAL} [INDEX | KEY] [index_name] (key_part,...) [index_option] ...
https://dev.mysql.com/doc/refman/8.4/en/invisible-indexes.html
MySQL supports invisible indexes; that is, indexes that are not used by the optimizer. If an index made invisible actually is needed or used by the optimizer, there are several ways to notice the effect of its absence on queries for the table: ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-option-tables.html
ndb-optimization-delay: Number of milliseconds to wait between processing sets of rows by OPTIMIZE TABLE on NDB tables. ndb_optimized_node_selection: Determines how SQL node chooses cluster data node to use as transaction coordinator. The following ...
https://dev.mysql.com/doc/relnotes/mysql/8.4/en/news-8-4-3.html
(Bug #36723117) InnoDB: FTS index optimization would sometimes not function correctly with tokens equal in collation order but different in terms of bytes. (Bug #36652127) InnoDB: Replaced std::this_thread::sleep_for(std::chrono::seconds(0)) usage ... C API Notes Compilation Notes Configuration Notes SQL Function and Operator Notes JavaScript Programs Performance Schema Notes sys Schema Notes Thread Pool Notes Functionality Added or Changed Bugs Fixed C API Notes The asynchronous interface used unsafe static local variables to store state ...
https://dev.mysql.com/doc/mysql-cluster-manager/8.4/en/mcm-attribute-tables-mysqld.html
ndb-optimization-delay: Number of milliseconds to wait between processing sets of rows by OPTIMIZE TABLE on NDB tables. ndb_optimized_node_selection: Determines how SQL node chooses cluster data node to use as transaction coordinator.
https://dev.mysql.com/doc/internals/en/x-protocol-use-cases-use-cases.html
Optimizing for Network Round-Trips (Assuming the MySQL Client/Server Protocol in this case) Network round-trips can be minimized by creating a huge SQL statements of up to 1Gbyte in chunks of 16Mbyte (the protocol's maximum frame size) and sending ... Topics in this section: Prepared Statements with Single Round-Trip Streaming Inserts SQL with Multiple Resultsets Inserting CRUD Data in a Batch Cross-Collection Update and Delete Prepared Statements with Single Round-Trip In the MySQL Client/Server Protocol, a PREPARE/EXECUTE cycle required two round-trips as the COM_STMT_EXECUTE requires data from the COM_STMT_PREPARE-ok ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/mem-features-qrti.html
Reading QRTi Values The queries listed on the Query Analyzer page also have a color-coded pie chart representing a breakdown of the values used in the QRTi calculation; green representing the optimal percentage, yellow the acceptable percentage, and ...It is a "quality of service" measurement for each query, and uses the Apdex formula for that calculation: Apdex on ...
https://dev.mysql.com/doc/heatwave-aws/en/heatwave-aws-relnotes.html
2025-05-29: Hypergraph Optimizer Default Setting The Hypergraph Optimizer is now enabled by default starting with MySQL 9.3.1, whose default value of optimizer_switch has hypergraph_optimizer=on. 2023-04-27: New Features Now Availability MySQL ...