Spec-Zone .ru
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ANALYZE [NO_WRITE_TO_BINLOG | LOCAL] TABLEtbl_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
14.2.4.2.10, "Persistent Optimizer Statistics for InnoDB Tables" and Section
14.2.7, "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
18.3.4, "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 , orwarning |
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
.