select dblink_connect('myconn','hostaddr=10.0.227.73 port=5432 dbname=pointer user=pointer password=pointer');

CREATE VIEW tt AS
SELECT *
    FROM dblink('myconn', 'select datadate from test')
    AS t1(S              bigint);

select dblink_get_connections();

--展示如下:
DB=# select dblink_get_connections();
  dblink_get_connections
--------------------------
 {myconn}

SELECT dblink_disconnect('myconn');