28.4.27 INFORMATION_SCHEMA INNODB_TEMP_TABLE_INFO 表
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
, andDB_ROLL_PTR
). -
SPACE
The ID of the temporary tablespace where the temporary table resides.
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
-
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 theSHOW COLUMNS
statement to view additional information about the columns of this table, including data types and default values.