SHOW LOCKS

SHOW_LOCKS returns a list of locks from across the cluster.

Read more about locks in Concurrency and Locks.

Syntax

SELECT SHOW_LOCKS()

Output

This function returns a list of active locks. If no locks are active in the cluster, the result set will be empty.

Parameter	Description
`stmt_id`	Statement ID that caused the lock.
`stmt_string`	Statement text
`username`	The role that executed the statement
`server`	The worker node’s IP
`port`	The worker node’s port
`locked_object`	The full qualified name of the object being locked, separated with `$` (e.g. `table$t$public$nba2` for table `nba2` in schema `public`, in database `t`
`lockmode`	The locking mode (inclusive or exclusive).
`statement_start_time`	Timestamp the statement started
`lock_start_time`	Timestamp the lock was obtained
`is_statement_active`	Is the statement causing the lock running or not
`is_snapshot_active`	Is the snapshot of the metadata keys, created by the statement, still active or not

Examples

SELECT SHOW_LOCKS();

Output:

statement id |statement string                  |username |server   |port |locked object  |lock mode |statement start time |lock start time    |is_statement_active |is_snapshot_active
-------------+----------------------------------+---------+---------+-----+---------------+----------+---------------------+-------------------+--------------------+------------------
2            |create or replace table t (x int);|sqream   |127.0.0.1|5000 |database$master|Inclusive |2024-07-04 15:07:02  |2024-07-04 15:07:02|1                   |1

Permissions

This utility function requires a CONNECT permission on the database level.