$PostgreSQL: pgsql/contrib/dblink/doc/connection,v 1.5 2007/07/08 17:12:38 joe Exp $
==================================================================
Name

dblink_connect -- Opens a persistent connection to a remote database

Synopsis

dblink_connect(text connstr)
dblink_connect(text connname, text connstr)

Inputs

  connname
    if 2 arguments are given, the first is used as a name for a persistent
    connection

  connstr

    standard libpq format connection string, 
    e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"

    if only one argument is given, the connection is unnamed; only one unnamed
    connection can exist at a time

Outputs

  Returns status = "OK"

Notes

  Only superusers may use dblink_connect to create non-password
  authenticated connections. If non-superusers need this capability,
  use dblink_connect_u instead.

Example usage

select dblink_connect('dbname=postgres');
 dblink_connect
----------------
 OK
(1 row)

select dblink_connect('myconn','dbname=postgres');
 dblink_connect
----------------
 OK
(1 row)

==================================================================
Name

dblink_connect_u -- Opens a persistent connection to a remote database

Synopsis

dblink_connect_u(text connstr)
dblink_connect_u(text connname, text connstr)

Inputs

  connname
    if 2 arguments are given, the first is used as a name for a persistent
    connection

  connstr

    standard libpq format connection string, 
    e.g. "hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd"

    if only one argument is given, the connection is unnamed; only one unnamed
    connection can exist at a time

Outputs

  Returns status = "OK"

Notes

  With dblink_connect_u, a non-superuser may connect to any database server
  using any authentication method. If the authentication method specified
  for a particular user does not require a password, impersonation and
  therefore escalation of privileges may occur. For this reason,
  dblink_connect_u is initially installed with all privileges revoked from
  public. Privilege to these functions should be granted with care.

Example usage


==================================================================
Name

dblink_disconnect -- Closes a persistent connection to a remote database

Synopsis

dblink_disconnect()
dblink_disconnect(text connname)

Inputs

  connname
    if an argument is given, it is used as a name for a persistent
    connection to close; otherwiase the unnamed connection is closed

Outputs

  Returns status = "OK"

Example usage

test=# select dblink_disconnect();
 dblink_disconnect
-------------------
 OK
(1 row)

select dblink_disconnect('myconn');
 dblink_disconnect
-------------------
 OK
(1 row)
