Updated on 2025-05-29 GMT+08:00

SNAPSHOT.SNAP_QUERY

The SNAP_QUERY table records information about SQL statements in all stored WDR snapshots. After a WDR snapshot is started (that is, the GUC parameter enable_wdr_snapshot is set to on), the SNAP_QUERY table is created, as shown in Table 1.

Table 1 SNAP_QUERY columns

Name

Type

Description

snap_node_name

name

Node name.

snap_node_id

integer

Node ID. The value is 0 in the current version.

snap_user_name

name

Username. If the user who runs the query statement does not exist, *REMOVED_USER* is displayed.

snap_user_id

oid

User OID.

snap_unique_sql_id

bigint

ID of the normalized SQL statement.

snap_query

text

Normalized SQL statement.

Note: The length is controlled by the GUC parameter track_activity_query_size.

snap_last_updated

timestamp with time zone

Last time when the statement was updated.

snap_parent_unique_sql_id

bigint

Unique ID of the parent SQL statement. The value is 0 for a non-stored procedure substatement.

snap_db_name

name

Name of the database connected to the backend. If the database where the query statement is executed does not exist, *REMOVED_DB* is displayed.

snap_db_id

db_id

OID of the database that the backend is connected to.