This is a read-only copy of the MariaDB Knowledgebase generated on 2024-12-22. For the latest, interactive version please visit https://mariadb.com/kb/.

mysql.innodb_index_stats

Contents

  1. Example
  2. See Also

The mysql.innodb_index_stats table stores data related to particular InnoDB Persistent Statistics, and contains multiple rows for each index.

This table, along with the related mysql.innodb_table_stats table, can be manually updated in order to force or test differing query optimization plans. After updating, FLUSH TABLE innodb_index_stats is required to load the changes.

mysql.innodb_index_stats is not replicated, although any ANALYZE TABLE statements on the table will be by default..

It contains the following fields:

FieldTypeNullKeyDefaultDescription
database_namevarchar(64)NOPRINULLDatabase name.
table_namevarchar(64)NOPRINULLTable, partition or subpartition name.
index_namevarchar(64)NOPRINULLIndex name.
last_updatetimestampNOcurrent_timestamp()Time that this row was last updated.
stat_namevarchar(64)NOPRINULLStatistic name.
stat_valuebigint(20) unsignedNONULLEstimated statistic value.
sample_sizebigint(20) unsignedYESNULLNumber of pages sampled for the estimated statistic value.
stat_descriptionvarchar(1024)NONULLStatistic description.

Example

SELECT * FROM mysql.innodb_index_stats\G
*************************** 1. row ***************************
   database_name: mysql
      table_name: gtid_slave_pos
      index_name: PRIMARY
     last_update: 2017-08-19 20:38:34
       stat_name: n_diff_pfx01
      stat_value: 0
     sample_size: 1
stat_description: domain_id
*************************** 2. row ***************************
   database_name: mysql
      table_name: gtid_slave_pos
      index_name: PRIMARY
     last_update: 2017-08-19 20:38:34
       stat_name: n_diff_pfx02
      stat_value: 0
     sample_size: 1
stat_description: domain_id,sub_id
*************************** 3. row ***************************
   database_name: mysql
      table_name: gtid_slave_pos
      index_name: PRIMARY
     last_update: 2017-08-19 20:38:34
       stat_name: n_leaf_pages
      stat_value: 1
     sample_size: NULL
stat_description: Number of leaf pages in the index
*************************** 4. row ***************************
   database_name: mysql
      table_name: gtid_slave_pos
      index_name: PRIMARY
     last_update: 2017-08-19 20:38:34
       stat_name: size
      stat_value: 1
     sample_size: NULL
stat_description: Number of pages in the index
*************************** 5. row ***************************
   database_name: test
      table_name: ft
      index_name: FTS_DOC_ID_INDEX
     last_update: 2017-09-15 12:58:39
       stat_name: n_diff_pfx01
      stat_value: 0
     sample_size: 1
stat_description: FTS_DOC_ID
*************************** 6. row ***************************
   database_name: test
      table_name: ft
      index_name: FTS_DOC_ID_INDEX
     last_update: 2017-09-15 12:58:39
       stat_name: n_leaf_pages
      stat_value: 1
     sample_size: NULL
stat_description: Number of leaf pages in the index
...

See Also

Content reproduced on this site is the property of its respective owners, and this content is not reviewed in advance by MariaDB. The views, information and opinions expressed by this content do not necessarily represent those of MariaDB or any other party.