28.4.27 The INFORMATION_SCHEMA INNODB_TEMP_TABLE_INFO Table

The INNODB_TEMP_TABLE_INFO table provides information about user-created InnoDB temporary tables that are active in an InnoDB instance. It does not provide information about internal InnoDB temporary tables used by the optimizer. The INNODB_TEMP_TABLE_INFO table is created when first queried, exists only in memory, and is not persisted to disk.

For usage information and examples, see Section 17.15.7, “InnoDB INFORMATION_SCHEMA Temporary Table Info Table”.

The INNODB_TEMP_TABLE_INFO table has these columns:

• TABLE_ID

  The table ID of the temporary table.

• NAME

  The name of the temporary table.

• N_COLS

  The number of columns in the temporary table. The number includes three hidden columns created by InnoDB (DB_ROW_ID, DB_TRX_ID, and DB_ROLL_PTR).

• SPACE

  The ID of the temporary tablespace where the temporary table resides.

Example

mysql> CREATE TEMPORARY TABLE t1 (c1 INT PRIMARY KEY) ENGINE=INNODB;

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_TEMP_TABLE_INFO\G
*************************** 1. row ***************************
TABLE_ID: 97
    NAME: #sql8c88_43_0
  N_COLS: 4
   SPACE: 76

Notes

• This table is useful primarily for expert-level monitoring.

• 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.