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The following table shows the contents of the data_locks  table for a system running a heavy workload. 

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## 15.15.2.2 InnoDB Lock and Lock-Wait Information 

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## Note 

This section describes locking information as exposed by the Performance Schema data_locks  and data_lock_waits  tables, which supersede the INFORMATION_SCHEMA INNODB_LOCKS  and INNODB_LOCK_WAITS tables in MySQL 8.0. For similar discussion written in terms of the older INFORMATION_SCHEMA  tables, see InnoDB Lock and Lock-Wait Information, in MySQL 5.7 Reference Manual. 

When a transaction updates a row in a table, or locks it with SELECT FOR UPDATE , InnoDB  establishes a list or queue of locks on that row. Similarly, InnoDB  maintains a list of locks on a table for table-level locks. If a second transaction wants to update a row or lock a table already locked by a prior transaction in an incompatible mode, InnoDB  adds a lock request for the row to the corresponding queue. For a lock to be 

