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MySQL Information Schema  /  INFORMATION_SCHEMA InnoDB Tables  /  The INFORMATION_SCHEMA INNODB_LOCK_WAITS Table

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.

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