Updated on 2023-10-23 GMT+08:00

PG_STAT_ACTIVITY

PG_STAT_ACTIVITY shows information about the current user's queries. The columns save information about the last query.

Table 1 PG_STAT_ACTIVITY columns

Name

Type

Description

datid

oid

OID of the database that the user session connects to in the backend

datname

name

Name of the database that the user session connects to in the backend

pid

bigint

ID of the backend thread

sessionid

bigint

Session ID

usesysid

oid

OID of the user logged in to the backend

usename

name

Name of the user logged in to the backend

application_name

text

Name of the application connected to the backend

client_addr

inet

IP address of the client connected to the backend. If this column is null, it indicates either the client is connected via a Unix socket on the server or this is an internal process, such as autovacuum.

client_hostname

text

Host name of the connected client, as reported by a reverse DNS lookup of client_addr. This column will be non-null only for IP connections and only when log_hostname is enabled.

client_port

integer

TCP port number that the client uses for communication with the backend (–1 if a Unix socket is used)

backend_start

timestamp with time zone

Time when this process was started, that is, when the client connected to the server

xact_start

timestamp with time zone

Time when current transaction was started (null if no transaction is active) If the current query is the first of its transaction, the value of this column is the same as that of the query_start column.

query_start

timestamp with time zone

Time when the currently active query was started, or time when the last query was started if the value of state is not active

state_change

timestamp with time zone

Time when state was last modified

waiting

boolean

Whether the backend is currently waiting for a lock. If yes, the value is true.

enqueue

text

Unsupported currently

state

text

Overall status of the backend. The value must be one of the following:
  • active: The backend is executing a query.
  • idle: The backend is waiting for a new client command.
  • idle in transaction: The backend is in a transaction, but there is no statement being executed in the transaction.
  • idle in transaction (aborted): The backend is in a transaction, but there are statements failed in the transaction.
  • fastpath function call: The backend is executing a fast-path function.
  • disabled: This state is reported if track_activities is disabled in this backend.
NOTE:

Common users can view their own session status only. The state information of other accounts is empty. For example, after user judy is connected to the database, the state information of user joe and the initial user omm in pg_stat_activity is empty.

SELECT datname, usename, usesysid, state,pid FROM pg_stat_activity;
 datname  | usename | usesysid | state  |       pid
----------+---------+----------+--------+-----------------
 postgres | omm     |       10 |        | 139968752121616
 postgres | omm     |       10 |        | 139968903116560
 db_tpcc | judy    |    16398 | active | 139968391403280
 postgres | omm     |       10 |        | 139968643069712
 postgres | omm     |       10 |        | 139968680818448
 postgres | joe     |    16390 |        | 139968563377936
(6 rows)

resource_pool

name

Resource pool used by the user

query_id

bigint

ID of a query

query

text

Latest query at the backend. If the value of state is active, this column shows the ongoing query. In all other states, it shows the last query that was executed.

connection_info

text

A string in JSON format recording the driver type, driver version, driver deployment path, and process owner of the connected database. For details, see connection_info.

unique_sql_id

bigint

Unique SQL statement ID.

trace_id

text

Driver-specific trace ID, which is associated with an application request.