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https://dev.mysql.com/doc/refman/8.4/en/information-schema-introduction.html
For information about using EXPLAIN output to tune INFORMATION_SCHEMA queries, see Section 10.2.3, “Optimizing INFORMATION_SCHEMA Queries”. INFORMATION_SCHEMA provides access to database metadata, information about the MySQL server such as the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-analyze-table-complexity.html
For more information, see Section 17.8.10.1, “Configuring Persistent Optimizer Statistics Parameters”. See Section 17.8.10.2, “Configuring Non-Persistent Optimizer Statistics Parameters” for additional information. ANALYZE TABLE complexity ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-benefits.html
When you design a database with appropriate primary key columns for each table, operations involving those columns are automatically optimized. Inserts, updates, and deletes are optimized by an automatic mechanism called change buffering. For ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-midpoint_insertion.html
You can control the insertion point in the LRU list and choose whether InnoDB applies the same optimization to blocks brought into the buffer pool by table or index scans. The optimization that keeps the buffer pool from being churned by read-ahead ... Rather than using a strict LRU algorithm, InnoDB uses a technique to minimize the amount of data that is brought into the buffer pool and never accessed ...
https://dev.mysql.com/doc/refman/8.4/en/internal-temporary-tables.html
Tables created for subquery or semijoin materialization (see Section 10.2.2, “Optimizing Subqueries, Derived Tables, View References, and Common Table Expressions”). To determine whether a statement requires a temporary table, use EXPLAIN and ...
https://dev.mysql.com/doc/refman/8.4/en/json-search-functions.html
Queries using JSON_CONTAINS() on InnoDB tables can be optimized using multi-valued indexes; see Multi-Valued Indexes, for more information. Queries on JSON columns of InnoDB tables using JSON_OVERLAPS() in the WHERE clause can be optimized using ...
https://dev.mysql.com/doc/refman/8.4/en/mathematical-functions.html
Thus, for optimizer purposes, RAND() is not a constant value and cannot be used for index optimizations. ABS(X) Returns the absolute value of X, or NULL if X is NULL. An implication of this is that ABS(-9223372036854775808) produces an error because ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-table-maintenance.html
You can use myisamchk to check, repair, or optimize database tables. This section discusses how to use myisamchk to check or repair MyISAM tables (tables that have .MYD and .MYI files for storing data and indexes). For general myisamchk background, ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations.html
The statements CHECK TABLE, OPTIMIZE TABLE, ANALYZE TABLE, and REPAIR TABLE are supported for partitioned tables. ANALYZE, CHECK, OPTIMIZE, REPAIR, and TRUNCATE operations are supported with subpartitions. This section discusses current ...
https://dev.mysql.com/doc/refman/8.4/en/row-subqueries.html
Scalar or column subqueries return a single value or a column of values. A row subquery is a subquery variant that returns a single row and can thus return more than one column value. If this row has col3 and col4 values equal to the col1 and col2 ...