13.7.2.1 ANALYZE TABLE Syntax

ANALYZE [NO_WRITE_TO_BINLOG | LOCAL] TABLE
    tbl_name [, tbl_name] ...

ANALYZE TABLE analyzes and stores the key distribution for a table. During the analysis, the table is locked with a read lock for InnoDB and MyISAM. This statement works with InnoDB, NDB, and MyISAM tables. For MyISAM tables, this statement is equivalent to using myisamchk --analyze.

For more information on how the analysis works within InnoDB, see Section 14.6.5.7, “Limits on InnoDB Tables”.

MySQL uses the stored key distribution to decide the order in which tables should be joined when you perform a join on something other than a constant. In addition, key distributions can be used when deciding which indexes to use for a specific table within a query.

This statement requires SELECT and INSERT privileges for the table.

Beginning with MySQL 5.1.27, ANALYZE TABLE is also supported for partitioned tables. Also beginning with MySQL 5.1.27, you can use ALTER TABLE ... ANALYZE PARTITION to analyze one or more partitions; for more information, see Section 13.1.7, “ALTER TABLE Syntax”, and Section 18.3.3, “Maintenance of Partitions”.

ANALYZE TABLE returns a result set with the following columns.

ColumnValue
TableThe table name
OpAlways analyze
Msg_typestatus, error, info, note, or warning
Msg_textAn informational message

You can check the stored key distribution with the SHOW INDEX statement. See Section 13.7.5.23, “SHOW INDEX Syntax”.

If the table has not changed since the last ANALYZE TABLE statement, the table is not analyzed again.

By default, the server writes ANALYZE TABLE statements to the binary log so that they replicate to replication slaves. To suppress logging, specify the optional NO_WRITE_TO_BINLOG keyword or its alias LOCAL.