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https://dev.mysql.com/doc/refman/8.4/en/set-resource-group.html
An alternative to SET RESOURCE GROUP is the RESOURCE_GROUP optimizer hint, which assigns individual statements to a resource group. SET RESOURCE GROUP group_name [FOR thread_id [, thread_id] ...] SET RESOURCE GROUP is used for resource group ...
https://dev.mysql.com/doc/refman/8.4/en/show-table-status.html
For InnoDB tables, the row count is only a rough estimate used in SQL optimization. The row count is only a rough estimate used in SQL optimization. SHOW TABLE STATUS [{FROM | IN} db_name] [LIKE 'pattern' | WHERE expr] SHOW TABLE STATUS works like ...
https://dev.mysql.com/doc/refman/8.4/en/slow-query-log.html
The slow query log can be used to find queries that take a long time to execute and are therefore candidates for optimization. Administrative statements include ALTER TABLE, ANALYZE TABLE, CHECK TABLE, CREATE INDEX, DROP INDEX, OPTIMIZE TABLE, and ... The slow query log consists of SQL statements that take more than long_query_time seconds to execute and require at least min_examined_row_limit rows to be ...
https://dev.mysql.com/doc/refman/8.4/en/sorted-index-builds.html
This method involved opening a B-tree cursor to find the insert position and then inserting entries into a B-tree page using an optimistic insert. Sorted Index Builds and Optimizer Statistics Sorted index builds may result in optimizer statistics ...
https://dev.mysql.com/doc/refman/8.4/en/source-installation.html
Building MySQL from the source code enables you to customize build parameters, compiler optimizations, and installation location. We put a great deal of effort into ensuring that our binaries are built with the best possible options for optimal ...
https://dev.mysql.com/doc/refman/8.4/en/subqueries.html
For information about how the optimizer handles subqueries, see Section 10.2.2, “Optimizing Subqueries, Derived Tables, View References, and Common Table Expressions”. All subquery forms and operations that the SQL standard requires are ...
https://dev.mysql.com/doc/refman/8.4/en/trace-general-structure.html
A trace follows the actual execution path very closely; for each join, there is a join preparation object, a join optimization object, and a join execution object. Calls to the range optimizer, cost evaluations, reasons why an access path is chosen ...Query transformations (IN to EXISTS, outer join to inner join, and so on), simplifications (elimination of clauses), and equality propagation are shown in ...
https://dev.mysql.com/doc/refman/8.4/en/upgrade-best-practices.html
MySQL supports upgrading between minor versions (within an LTS series) and to the next major version (across an LTS series). LTS releases have 8+ years of support and are meant for production use. Performing a minor version upgrade is ...
https://dev.mysql.com/doc/refman/8.4/en/view-algorithms.html
If no ALGORITHM clause is present, the default algorithm is determined by the value of the derived_merge flag of the optimizer_switch system variable. For additional discussion, see Section 10.2.2.4, “Optimizing Derived Tables, View References, ...
https://dev.mysql.com/doc/refman/8.4/en/window-functions.html
For information about optimization and window functions, see Section 10.2.1.21, “Window Function Optimization”. MySQL supports window functions that, for each row from a query, perform a calculation using rows related to that row. The following ...