28.4.22 The INFORMATION_SCHEMA INNODB_SESSION_TEMP

28.4.22 The INFORMATION_SCHEMA INNODB_SESSION_TEMP_TABLESPACES Table

The INNODB_SESSION_TEMP_TABLESPACES table provides metadata about session temporary tablespaces used for internal and user-created temporary tables. This table was added in MySQL 8.0.13.

The INNODB_SESSION_TEMP_TABLESPACES table has these columns:

ID
The process or session ID.
SPACE
The tablespace ID. A range of 400 thousand space IDs is reserved for session temporary tablespaces. Session temporary tablespaces are recreated each time the server is started. Space IDs are not persisted when the server is shut down and may be reused.
PATH
The tablespace data file path. A session temporary tablespace has an ibt file extension.
SIZE
The size of the tablespace, in bytes.
STATE
The state of the tablespace. ACTIVE indicates that the tablespace is currently used by a session. INACTIVE indicates that the tablespace is in the pool of available session temporary tablespaces.
PURPOSE
The purpose of the tablespace. INTRINSIC indicates that the tablespace is used for optimized internal temporary tables use by the optimizer. SLAVE indicates that the tablespace is allocated for storing user-created temporary tables on a replication slave. USER indicates that the tablespace is used for user-created temporary tables. NONE indicates that the tablespace is not in use.

Example

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_SESSION_TEMP_TABLESPACES;
+----+------------+----------------------------+-------+----------+-----------+
| ID | SPACE      | PATH                       | SIZE  | STATE    | PURPOSE   |
+----+------------+----------------------------+-------+----------+-----------+
|  8 | 4294566162 | ./#innodb_temp/temp_10.ibt | 81920 | ACTIVE   | INTRINSIC |
|  8 | 4294566161 | ./#innodb_temp/temp_9.ibt  | 98304 | ACTIVE   | USER      |
|  0 | 4294566153 | ./#innodb_temp/temp_1.ibt  | 81920 | INACTIVE | NONE      |
|  0 | 4294566154 | ./#innodb_temp/temp_2.ibt  | 81920 | INACTIVE | NONE      |
|  0 | 4294566155 | ./#innodb_temp/temp_3.ibt  | 81920 | INACTIVE | NONE      |
|  0 | 4294566156 | ./#innodb_temp/temp_4.ibt  | 81920 | INACTIVE | NONE      |
|  0 | 4294566157 | ./#innodb_temp/temp_5.ibt  | 81920 | INACTIVE | NONE      |
|  0 | 4294566158 | ./#innodb_temp/temp_6.ibt  | 81920 | INACTIVE | NONE      |
|  0 | 4294566159 | ./#innodb_temp/temp_7.ibt  | 81920 | INACTIVE | NONE      |
|  0 | 4294566160 | ./#innodb_temp/temp_8.ibt  | 81920 | INACTIVE | NONE      |
+----+------------+----------------------------+-------+----------+-----------+

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.