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https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-operations.html
mysql> SELECT NAME, TOTAL_ROW_VERSIONS FROM INFORMATION_SCHEMA.INNODB_TABLES WHERE NAME LIKE 'test/t1'; +---------+--------------------+ | NAME | TOTAL_ROW_VERSIONS | +---------+--------------------+ | test/t1 | 0 | +---------+--------------------+ ... Online support details, syntax examples, and usage notes for DDL operations are provided under the following topics in this ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-maintenance.html
Table maintenance of partitioned tables can be accomplished using the statements CHECK TABLE, OPTIMIZE TABLE, ANALYZE TABLE, and REPAIR TABLE, which are supported for partitioned tables. OPTIMIZE PARTITION to reclaim any unused space and to ... A ...
https://dev.mysql.com/doc/internals/en/implementing-info-method.html
Prior to commencing a table scan, the [custom-engine.html#custom-engine-api-reference-info info()] method is called to provide extra table information to the optimizer. The information required by the optimizer is not given through return values ...
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-8-3-0.html
(WL #15294) INFORMATION_SCHEMA Notes When running OPTIMIZE TABLE on a table with a FULLTEXT index, the index was not fully optimized at the expected time, and thus an extra pass was required. (WL #15733) Optimizer Notes The hashing algorithm ...(Bug ...
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 ...