3.8、向前提取x行数据

postgres=# FETCH FORWARD 2 from tbase_cur ;             
 id |  nickname   
----+-------------
  1 | hello TBase
  2 | TBase好
(2 rows)
postgres=# FETCH FORWARD 2 from tbase_cur ; 
 id |   nickname    
----+---------------
  3 | TBase好
  4 | TBase default
(2 rows)