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. This statement does not work with views.
For more information on how the analysis works within
InnoDB, see
Section 14.6.11.1, “Configuring Persistent Optimizer Statistics Parameters” and
Section 14.6.11.3, “Estimating ANALYZE TABLE Complexity for InnoDB Tables”. Also see
Section 14.8.8, “Limits on InnoDB Tables”. In particular, when you
enable the
innodb_stats_persistent option,
you must run ANALYZE TABLE after loading
substantial data into an InnoDB table, or
creating a new index for one.
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.
ANALYZE TABLE is supported for partitioned
tables, and 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 19.3.4, “Maintenance of Partitions”.
In MySQL 5.6.11 only, gtid_next
must be set to AUTOMATIC before issuing this
statement. (Bug #16062608, Bug #16715809, Bug #69045)
ANALYZE TABLE returns a result set with the
following columns.
| Column | Value |
|---|---|
Table | The table name |
Op | Always analyze |
Msg_type | status, error,
info, note, or
warning |
Msg_text | An 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.