dblink_connect — opens a persistent connection to a remote databasedblink_connect_u — opens a persistent connection to a remote database, insecurelydblink_disconnect — closes a persistent connection to a remote databasedblink — executes a query in a remote databasedblink_exec — executes a command in a remote databasedblink_open — opens a cursor in a remote databasedblink_fetch — returns rows from an open cursor in a remote databasedblink_close — closes a cursor in a remote databasedblink_get_connections — returns the names of all open named dblink connectionsdblink_error_message — gets last error message on the named connectiondblink_send_query — sends an async query to a remote databasedblink_is_busy — checks if connection is busy with an async querydblink_get_notify — retrieve async notifications on a connectiondblink_get_result — gets an async query resultdblink_cancel_query — cancels any active query on the named connectiondblink_get_pkey — returns the positions and field names of a relation's primary key fields dblink_build_sql_insert — builds an INSERT statement using a local tuple, replacing the primary key field values with alternative supplied values dblink_build_sql_delete — builds a DELETE statement using supplied values for primary key field values dblink_build_sql_update — builds an UPDATE statement using a local tuple, replacing the primary key field values with alternative supplied values

dblink is a module that supports connections to other PostgreSQL databases from within a database session.

See also postgres_fdw, which provides roughly the same functionality using a more modern and standards-compliant infrastructure.