28.4.24 The INFORMATION_SCHEMA INNODB

28.4.24 The INFORMATION_SCHEMA INNODB_TABLESPACES Table

The INNODB_TABLESPACES table provides metadata about InnoDB file-per-table, general, and undo tablespaces.

For related usage information and examples, see Section 17.15.3, “InnoDB INFORMATION_SCHEMA Schema Object Tables”.

Note

The INFORMATION_SCHEMA FILES table reports metadata for InnoDB tablespace types including file-per-table tablespaces, general tablespaces, the system tablespace, the global temporary tablespace, and undo tablespaces.

The INNODB_TABLESPACES table has these columns:

SPACE
The tablespace ID.
NAME
The schema (database) and table name.
FLAG
A numeric value that represents bit-level information about tablespace format and storage characteristics.
ROW_FORMAT
The tablespace row format (Compact or Redundant, Dynamic or Compressed, or Undo). The data in this column is interpreted from the tablespace flag information that resides in the data file.
There is no way to determine from this flag information if the tablespace row format is Redundant or Compact, which is why one of the possible ROW_FORMAT values is Compact or Redundant.
PAGE_SIZE
The tablespace page size. The data in this column is interpreted from the tablespace flags information that resides in the .ibd file.
ZIP_PAGE_SIZE
The tablespace zip page size. The data in this column is interpreted from the tablespace flags information that resides in the .ibd file.
SPACE_TYPE
The type of tablespace. Possible values include General for general tablespaces, Single for file-per-table tablespaces, System for the system tablespace, and Undo for undo tablespaces.
FS_BLOCK_SIZE
The file system block size, which is the unit size used for hole punching. This column pertains to the InnoDB transparent page compression feature.
FILE_SIZE
The apparent size of the file, which represents the maximum size of the file, uncompressed. This column pertains to the InnoDB transparent page compression feature.
ALLOCATED_SIZE
The actual size of the file, which is the amount of space allocated on disk. This column pertains to the InnoDB transparent page compression feature.
AUTOEXTEND_SIZE
The auto-extend size of the tablespace. This column was added in MySQL 8.0.23.
SERVER_VERSION
The MySQL version that created the tablespace, or the MySQL version into which the tablespace was imported, or the version of the last major MySQL version upgrade. The value is unchanged by a release series upgrade, such as an upgrade from MySQL 8.0.x to 8.0.y. The value can be considered a “creation” marker or “certified” marker for the tablespace.
SPACE_VERSION
The tablespace version, used to track changes to the tablespace format.
ENCRYPTION
Whether the tablespace is encrypted. This column was added in MySQL 8.0.13.
STATE
The tablespace state. This column was added in MySQL 8.0.14.
For file-per-table and general tablespaces, states include:
- normal: The tablespace is normal and active.
- discarded: The tablespace was discarded by an ALTER TABLE ... DISCARD TABLESPACE statement.
- corrupted: The tablespace is identified by InnoDB as corrupted.
For undo tablespaces, states include:
- active: Rollback segments in the undo tablespace can be allocated to new transactions.
- inactive: Rollback segments in the undo tablespace are no longer used by new transactions. The truncate process is in progress. The undo tablespace was either selected by the purge thread implicitly or was made inactive by an ALTER UNDO TABLESPACE ... SET INACTIVE statement.
- empty: The undo tablespace was truncated and is no longer active. It is ready to be dropped or made active again by an ALTER UNDO TABLESPACE ... SET INACTIVE statement.

Example

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_TABLESPACES WHERE SPACE = 26\G
*************************** 1. row ***************************
         SPACE: 26
          NAME: test/t1
          FLAG: 0
    ROW_FORMAT: Compact or Redundant
     PAGE_SIZE: 16384
 ZIP_PAGE_SIZE: 0
    SPACE_TYPE: Single
 FS_BLOCK_SIZE: 4096
     FILE_SIZE: 98304
ALLOCATED_SIZE: 65536
AUTOEXTEND_SIZE: 0
SERVER_VERSION: 8.0.23
 SPACE_VERSION: 1
    ENCRYPTION: N
         STATE: normal

Notes

You must have the PROCESS privilege to query this table.
Use the INFORMATION_SCHEMA COLUMNS table or the SHOW COLUMNS statement to view additional information about the columns of this table, including data types and default values.