14.16.8 Retrieving InnoDB Tablespace Metadata from INFORMATION_SCHEMA.FILES

The Information Schema FILES table provides metadata about all InnoDB tablespace types including file-per-table tablespaces, general tablespaces, the system tablespace, temporary table tablespaces, and undo tablespaces (if present).

This section provides InnoDB-specific usage examples. For more information, see Section 24.3.9, “The INFORMATION_SCHEMA FILES Table”.

Note

The INNODB_SYS_TABLESPACES and INNODB_SYS_DATAFILES tables also provide metadata about InnoDB tablespaces, but data is limited to file-per-table and general tablespaces.

This query retrieves metadata about the InnoDB system tablespace from columns of the Information Schema FILES table that are pertinent to InnoDB tablespaces. FILES columns that are not relevant to InnoDB always return NULL, and are excluded from the query.

mysql> SELECT FILE_ID, FILE_NAME, FILE_TYPE, TABLESPACE_NAME, FREE_EXTENTS,
       TOTAL_EXTENTS,  EXTENT_SIZE, INITIAL_SIZE, MAXIMUM_SIZE, AUTOEXTEND_SIZE, DATA_FREE, STATUS ENGINE
       FROM INFORMATION_SCHEMA.FILES WHERE TABLESPACE_NAME LIKE 'innodb_system' \G
*************************** 1. row ***************************
        FILE_ID: 0
      FILE_NAME: ./ibdata1
      FILE_TYPE: TABLESPACE
TABLESPACE_NAME: innodb_system
   FREE_EXTENTS: 0
  TOTAL_EXTENTS: 12
    EXTENT_SIZE: 1048576
   INITIAL_SIZE: 12582912
   MAXIMUM_SIZE: NULL
AUTOEXTEND_SIZE: 67108864
      DATA_FREE: 4194304
         ENGINE: NORMAL

This query retrieves the FILE_ID (equivalent to the space ID) and the FILE_NAME (which includes path information) for InnoDB file-per-table and general tablespaces. File-per-table and general tablespaces have a .ibd file extension.

mysql> SELECT FILE_ID, FILE_NAME FROM INFORMATION_SCHEMA.FILES
       WHERE FILE_NAME LIKE '%.ibd%' ORDER BY FILE_ID;
    +---------+---------------------------------------+
    | FILE_ID | FILE_NAME                             |
    +---------+---------------------------------------+
    |       2 | ./mysql/plugin.ibd                    |
    |       3 | ./mysql/servers.ibd                   |
    |       4 | ./mysql/help_topic.ibd                |
    |       5 | ./mysql/help_category.ibd             |
    |       6 | ./mysql/help_relation.ibd             |
    |       7 | ./mysql/help_keyword.ibd              |
    |       8 | ./mysql/time_zone_name.ibd            |
    |       9 | ./mysql/time_zone.ibd                 |
    |      10 | ./mysql/time_zone_transition.ibd      |
    |      11 | ./mysql/time_zone_transition_type.ibd |
    |      12 | ./mysql/time_zone_leap_second.ibd     |
    |      13 | ./mysql/innodb_table_stats.ibd        |
    |      14 | ./mysql/innodb_index_stats.ibd        |
    |      15 | ./mysql/slave_relay_log_info.ibd      |
    |      16 | ./mysql/slave_master_info.ibd         |
    |      17 | ./mysql/slave_worker_info.ibd         |
    |      18 | ./mysql/gtid_executed.ibd             |
    |      19 | ./mysql/server_cost.ibd               |
    |      20 | ./mysql/engine_cost.ibd               |
    |      21 | ./sys/sys_config.ibd                  |
    |      23 | ./test/t1.ibd                         |
    |      26 | /home/user/test/test/t2.ibd           |
    +---------+---------------------------------------+

This query retrieves the FILE_ID and FILE_NAME for InnoDB temporary tablespaces. Temporary tablespace file names are prefixed by ibtmp.

mysql> SELECT FILE_ID, FILE_NAME FROM INFORMATION_SCHEMA.FILES
       WHERE FILE_NAME LIKE '%ibtmp%';
+---------+-----------+
| FILE_ID | FILE_NAME |
+---------+-----------+
|      22 | ./ibtmp1  |
+---------+-----------+

Similarly, InnoDB undo tablespace file names are prefixed by undo. The following query returns the FILE_ID and FILE_NAME for InnoDB undo tablespaces, if separate undo tablespaces are configured.

mysql> SELECT FILE_ID, FILE_NAME FROM INFORMATION_SCHEMA.FILES
       WHERE FILE_NAME LIKE '%undo%';