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https://dev.mysql.com/doc/refman/8.4/en/optimizer-statistics.html
The column_statistics data dictionary table stores histogram statistics about column values, for use by the optimizer in constructing query execution plans. The column_statistics table has these characteristics: The table contains statistics for ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-consumer-configurations.html
The consumer settings in the setup_consumers table form a hierarchy from higher levels to lower. The following discussion describes how consumers work, showing specific configurations and their effects as consumer settings are enabled progressively ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-setup-objects-table.html
The setup_objects table controls whether the Performance Schema monitors particular objects. This table has a maximum size of 100 rows by default. To change the table size, modify the performance_schema_setup_objects_size system variable at server ...
https://dev.mysql.com/doc/refman/8.4/en/rename-table.html
RENAME TABLE tbl_name TO new_tbl_name [, tbl_name2 TO new_tbl_name2] ... You must have ALTER and DROP privileges for the original table, and CREATE and INSERT privileges for the new table. You can rename tables locked with a LOCK TABLES statement, ...
https://dev.mysql.com/doc/refman/8.4/en/replication-features-optimizer.html
It is possible for the data on the source and replica to become different if a statement is written in such a way that the data modification is nondeterministic; that is, left up the query optimizer. (In general, this is not a good practice, even ...
https://dev.mysql.com/doc/refman/8.4/en/replication-features-row-searches.html
When a replica using row-based replication format applies an UPDATE or DELETE operation, it must search the relevant table for the matching rows. The algorithm used to carry out this process uses one of the table's indexes to carry out the search ...
https://dev.mysql.com/doc/refman/8.4/en/replication-gtids-auto-positioning.html
GTIDs replace the file-offset pairs previously required to determine points for starting, stopping, or resuming the flow of data between source and replica. When GTIDs are in use, all the information that the replica needs for synchronizing with ...
https://dev.mysql.com/doc/refman/8.4/en/sorted-index-builds.html
InnoDB performs a bulk load instead of inserting one index record at a time when creating or rebuilding indexes. This method of index creation is also known as a sorted index build. In the first phase, the clustered index is scanned, and index ...
https://dev.mysql.com/doc/refman/8.4/en/spatial-aggregate-functions.html
MySQL supports aggregate functions that perform a calculation on a set of values. For general information about these functions, see Section 14.19.1, “Aggregate Function Descriptions”. ST_Collect() can be used as a window function, as signified ...
https://dev.mysql.com/doc/refman/8.4/en/spatial-convenience-functions.html
The functions in this section provide convenience operations on geometry values. Unless otherwise specified, functions in this section handle their geometry arguments as follows: If any argument is NULL, the return value is NULL. If any geometry ...