CLEAN CONNECTION

CLEAN CONNECTION — Clean up pooler connections in a cluster

Synopsis

CLEAN CONNECTION TO { COORDINATOR ( nodename [, ... ] ) | NODE ( nodename [, ... ] ) | ALL {FORCE} }
    [ FOR DATABASE dbname ]
    [ TO USER username ]

Description

CLEAN CONNECTION cleans pooler connections in a Postgres-XL cluster. This can be done for a given database or role. This command's usage is restricted to superusers. It is possible to clean connections to a list of Postgres-XL Coordinators or Datanodes. If TO ALL is specified, connections to all the nodes are cleaned. A username or a dbname has to be specified to perform CLEAN CONNECTION.

Parameters

FORCE

It can only be specified with the clause TO ALL. If specified, all the backends connected to the specified node(s) are closed by sending to them a signal SIGTERM.

dbname

If specified in the optional clause FOR DATABASE, pooler connections are cleaned for given database.

username

If specified in the optional clause TO USER, pooler connections are cleaned for the given role.

nodename

In the case of cleaning connections to a given list of Coordinators, nodename has to be specified with the clause TO COORDINATOR .

In the case of cleaning connections to a given list of Datanodes, nodename has to be specified with the clause TO NODE .

num can contain a list of nodes like in the query:

CLEAN CONNECTION TO COORDINATOR coord1,coord2 FOR DATABASEname;

to clean connections to Coordinators coord1 and coord2.

Examples

Cleaning connection to Datanodes dn1 and dn2 for database template1:

CLEAN CONNECTION TO NODE dn1,dn2 FOR DATABASE template1;

Cleaning connection to Datanode dn3 for role postgres:

CLEAN CONNECTION TO NODE dn3 TO USER postgres;

Cleaning connection to all nodes on database postgres for role admin and cut connections to backends.

CLEAN CONNECTION TO ALL FORCE FOR DATABASE postgres TO USER admin;

Compatibility

CLEAN CONNECTION does not conform to the SQL standards, it is a Postgres-XL specific command.