MySQL 9.3 Reference Manual Including MySQL NDB Cluster 9.3
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”.
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.
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 8.4.x
to
8.4.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.
STATE
The tablespace state.
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.
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: 8.4.0
SPACE_VERSION: 1
ENCRYPTION: N
STATE: normal
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.