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https://dev.mysql.com/doc/refman/8.4/en/subqueries.html
A subquery can contain many of the keywords or clauses that an ordinary SELECT can contain: DISTINCT, GROUP BY, ORDER BY, LIMIT, joins, index hints, UNION constructs, comments, functions, and so on. All subquery forms and operations that the SQL ...
https://dev.mysql.com/doc/refman/8.4/en/subquery-restrictions.html
In general, you may be able to influence the optimizer to materialize a derived table by adding a NO_MERGE optimizer hint. In general, you cannot modify a table and select from the same table in a subquery. For example, this limitation applies to ...
https://dev.mysql.com/doc/refman/8.4/en/update.html
UPDATE is a DML statement that modifies rows in a table. An UPDATE statement can start with a WITH clause to define common table expressions accessible within the UPDATE. Single-table syntax: UPDATE [LOW_PRIORITY] [IGNORE] table_reference SET ...
https://dev.mysql.com/doc/refman/8.4/en/version-tokens-reference.html
System variables: version_tokens_session Command-Line Format --version-tokens-session=value System Variable version_tokens_session Scope Global, Session Dynamic Yes SET_VAR Hint Applies No Type String Default Value NULL The session value of this ...
https://dev.mysql.com/doc/refman/8.4/en/view-restrictions.html
Views do not have indexes, so index hints do not apply. Use of index hints when selecting from a view is not permitted. The maximum number of tables that can be referenced in the definition of a view is 61. View processing is not optimized: It is ...
https://dev.mysql.com/doc/refman/8.4/en/with.html
The MAX_EXECUTION_TIME optimizer hint enforces a per-query execution timeout for the SELECT statement in which it appears. A common table expression (CTE) is a named temporary result set that exists within the scope of a single statement and that ...
https://dev.mysql.com/doc/refman/8.4/en/derived-condition-pushdown-optimization.html
If this optimization is disabled by optimizer_switch, you can enable it for a specific query using the DERIVED_CONDITION_PUSHDOWN optimizer hint. To disable the optimization for a given query, use the NO_DERIVED_CONDITION_PUSHDOWN optimizer hint.
https://dev.mysql.com/doc/refman/8.4/en/invisible-indexes.html
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: Errors occur for queries that include index hints that refer to the invisible index. Using ... MySQL supports invisible indexes; that is, indexes that are not used by the ...
https://dev.mysql.com/doc/refman/8.4/en/fulltext-restrictions.html
Index hints are more limited for FULLTEXT searches than for non-FULLTEXT searches. Full-text searches are supported for InnoDB and MyISAM tables only. The exception is that for Unicode, the utf8mb3 or utf8mb4 character set can be used, but not the ...
https://dev.mysql.com/doc/refman/8.4/en/index-merge-optimization.html
In addition to using the optimizer_switch system variable to control optimizer use of the Index Merge algorithms session-wide, MySQL supports optimizer hints to influence the optimizer on a per-statement basis. The Index Merge access method ...