5.15 The INFORMATION_SCHEMA INNODB_LOCK_WAITS Table

The INNODB_LOCK_WAITS table contains one or more rows for each blocked InnoDB transaction, indicating the lock it has requested and any locks that are blocking that request.

Note

This table is deprecated as of MySQL 5.7.14 and is removed in MySQL 8.0.

The INNODB_LOCK_WAITS table has these columns:

• REQUESTING_TRX_ID

  The ID of the requesting (blocked) transaction.

• REQUESTED_LOCK_ID

  The ID of the lock for which a transaction is waiting. To obtain details about the lock, join this column with the LOCK_ID column of the INNODB_LOCKS table.

• BLOCKING_TRX_ID

  The ID of the blocking transaction.

• BLOCKING_LOCK_ID

  The ID of a lock held by a transaction blocking another transaction from proceeding. To obtain details about the lock, join this column with the LOCK_ID column of the INNODB_LOCKS table.

Example

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCK_WAITS\G
*************************** 1. row ***************************
requesting_trx_id: 3396
requested_lock_id: 3396:91:3:2
  blocking_trx_id: 3395
 blocking_lock_id: 3395:91:3:2

Notes

• Use this table to help diagnose performance problems that occur during times of heavy concurrent load. Its contents are updated as described in Persistence and Consistency of InnoDB Transaction and Locking Information.

• 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.

• For usage information, see Using InnoDB Transaction and Locking Information.