Help Center/ Data Warehouse Service/ Standard Data Warehouse (9.1.0.x)/ GaussDB(DWS) System Catalogs and Views/ System Views/ PG_LOCKS
Updated on 2025-06-12 GMT+08:00
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PG_LOCKS

PG_LOCKS displays information about the locks held by open transactions.

Table 1 PG_LOCKS columns

Column

Type

Reference

Description

locktype

Text

N/A

Type of the locked object: relation, extend, page, tuple, transactionid, virtualxid, object, userlock, and advisory

database

OID

PG_DATABASE.oid

OID of the database in which the locked target exists

  • The OID is 0 if the target is a shared object.
  • The OID is NULL if the locked target is a transaction.

relation

OID

PG_CLASS.oid

OID of the relationship targeted by the lock. The value is NULL if the object is neither a relationship nor part of a relationship.

page

Integer

N/A

Page number targeted by the lock within the relationship. If the object is neither a relation page nor row page, the value is NULL.

tuple

Smallint

N/A

Row number targeted by the lock within the page. If the object is not a row, the value is NULL.

virtualxid

Text

N/A

Virtual ID of the transaction targeted by the lock. If the object is not a virtual transaction ID, the value is NULL.

transactionid

Xid

N/A

ID of the transaction targeted by the lock. If the object is not a transaction ID, the value is NULL.

classid

OID

PG_CLASS.oid

OID of the system table that contains the object. If the object is not a general database object, the value is NULL.

objid

OID

N/A

OID of the lock target within its system table. If the target is not a general database object, the value is NULL.

objsubid

Smallint

N/A

Column number for a column in the table. The value is 0 if the target is some other object type. If the object is not a general database object, the value is NULL.

virtualtransaction

Text

N/A

Virtual ID of the transaction holding or awaiting this lock

pid

Bigint

N/A

Logical ID of the server thread holding or awaiting this lock. This is NULL if the lock is held by a prepared transaction.

mode

Text

N/A

Lock mode held or desired by this thread For more information about lock modes, see LOCK.

granted

boolean

N/A
  • The value is true if the lock is a held lock.
  • The value is false if the lock is an awaited lock.

fastpath

boolean

N/A

Whether the lock is obtained through fast-path (true) or main lock table (false)

waittime

Timestamp with time zone

N/A

Timestamp when the lock wait starts.

This column is available only in clusters of version 9.1.0.200 or later.

holdtime

Timestamp with time zone

N/A

Timestamp when the lock starts to be held. This column is available only in clusters of version 9.1.0.200 or later.
Parent Topic: System Views