PostgreSQLで関数は普通こんな形でselect以下に書いて実行します。 
postgres=# select sqrt(144);
 sqrt 
------
   12
(1 row)
普通の関数は上のでＯＫ
しかし、record型を返す関数の場合はこの形で指定するとレコードがすべて１カラムに入って帰ってくるのでみずらい 
postgres=# select pg_get_keywords();
                         pg_get_keywords                          
------------------------------------------------------------------
 (abort,U,unreserved)
 (absolute,U,unreserved)
 (access,U,unreserved)
 (action,U,unreserved)
 (add,U,unreserved)
 (admin,U,unreserved)
 (after,U,unreserved)
 (aggregate,U,unreserved)
 (all,R,reserved)
 (also,U,unreserved)
where句に入れるとレコードで帰ってくるよ
みやすい！ 
postgres=# select * from pg_get_keywords();
       word        | catcode |                   catdesc                    
-------------------+---------+----------------------------------------------
 abort             | U       | unreserved
 absolute          | U       | unreserved
 access            | U       | unreserved
 action            | U       | unreserved
 add               | U       | unreserved
 admin             | U       | unreserved
 after             | U       | unreserved
 aggregate         | U       | unreserved
 all               | R       | reserved
 also              | U       | unreserved