信息模式 FILES 表提供关于所有 InnoDB 表空间类型的元数据，包括 按表分文件表空间、通用表空间、系统表空间、临时表表空间以及 回滚表空间（如果存在）。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 about data provided by the Information Schema FILES table, see 第 28.3.15 节，“INFORMATION_SCHEMA FILES 表”.This section provides InnoDB-specific usage examples. For more information about data provided by the Information Schema FILES table, see Section 28.3.15, “The INFORMATION_SCHEMA FILES Table”.

This query retrieves metadata about the InnoDB system tablespace from fields 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

此查询检索 FILE_ID（相当于空间 ID）和 FILE_NAME（包括路径信息），适用于 InnoDB 的每表文件和通用表空间。每表文件和通用表空间的文件扩展名为 .ibd。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           |
    +---------+---------------------------------------+

此查询检索 FILE_ID 和 FILE_NAME，适用于 InnoDB 全局临时表空间。全局临时表空间的文件名前缀为 ibtmp。This query retrieves the FILE_ID and FILE_NAME for the InnoDB global temporary tablespace. Global 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  |
+---------+-----------+

类似地，InnoDB 回滚（undo）表空间的文件名前缀为 undo。以下查询返回 FILE_ID 和 FILE_NAME，适用于 InnoDB 回滚表空间。Similarly, InnoDB undo tablespace file names are prefixed by undo. The following query returns the FILE_ID and FILE_NAME for InnoDB undo tablespaces.

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