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https://dev.mysql.com/doc/refman/8.4/en/controlling-optimizer.html
The server maintains histogram statistics about column values in the column_statistics data dictionary table (see Section 10.9.6, “Optimizer Statistics”). Instead, you can obtain histogram information by querying ... MySQL provides optimizer ...
https://dev.mysql.com/doc/refman/8.4/en/general-thread-states.html
statistics The server is calculating statistics to develop a query execution plan. The following list describes thread State values that are associated with general query processing and not more specialized activities such as replication. Many of ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-tuning-monitoring.html
The information in these tables is system-wide: it summarizes the compression statistics across all compressed tables in your database. The key statistics to consider are the number of, and amount of time spent performing, compression and ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-read_ahead.html
The SHOW ENGINE INNODB STATUS statement displays statistics to help you evaluate the effectiveness of the read-ahead algorithm. Statistics include counter information for the following global status variables: Innodb_buffer_pool_read_ahead ... A ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-table-import.html
7f34d9a37700 InnoDB: cannot calculate statistics for table "test"."t1" because the .ibd file is missing. This section describes how to import tables using the Transportable Tablespaces feature, which permits importing tables, partitioned tables, or ...
https://dev.mysql.com/doc/refman/8.4/en/invisible-indexes.html
ALTER INDEX operation: ALTER TABLE t1 ALTER INDEX i_idx INVISIBLE; ALTER TABLE t1 ALTER INDEX i_idx VISIBLE; Information about whether an index is visible or invisible is available from the Information Schema STATISTICS table or SHOW INDEX output.
https://dev.mysql.com/doc/refman/8.4/en/miscellaneous-optimization-tips.html
If possible, classify reports as “live” or as “statistical”, where data needed for statistical reports is created only from summary tables that are generated periodically from the live data. This section lists a number of miscellaneous tips ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-ftdump.html
--count, -c Command-Line Format --count Calculate per-word statistics (counts and global weights). It reads the MyISAM index file directly, so it must be run on the server host where the table is located. Before using myisam_ftdump, be sure to issue ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-storage-engine.html
myisamchk --analyze stores statistics for portions of keys, as well as for entire keys. MyISAM is based on the older (and no longer available) ISAM storage engine but has many useful extensions. Table 18.2 MyISAM Storage Engine Features Feature ...
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-general-options.html
stats_method influences how NULL values are treated for index statistics collection when the --analyze option is given. For more information, see the description of myisam_stats_method in Section 7.1.8, “Server System Variables”, and Section ...