sql - Sql查询——Oracle数据库

Question

empid    emplrcd   effdt   effsq
101          #1    2/1/99    0
101          #1    3/1/13    1
101          #1    23/3/13   1 
101          #1    22/6/13   2
102          #2    20/6/91   1

我需要检索第 4 行，并且我已经编写了部分代码，请帮助我完成另一半。

select a* 
from Ps_Job a 
where a.empid = '101' 
and a.emprcd ='#1' 
and a.effdt = (select max(a1.effdt) from Psjob1) where...............
and a.effseq = (Select  max(a2.effseq) from Ps_job2)
where..............

请帮我解决应该是通用的而不是特定于行的原因。我认为它应该充满 nth max 概念，但不确定。

Answer 1

在甲骨文中

select *
from 
(select a*  from Ps_Job a 
  where a.empid = '101' 
  and a.emprcd ='#1' 
  and a.effdt = (select max(a1.effdt) from Psjob1)  where ... 
  and a.effseq = (Select  max(a2.effseq) from Ps_job2)
  where ..... ) 
where ROWNUM == **The line number what you want to get**;

在 sql

SELECT * from Ps_Job LIMIT 3,1where(

     select a*  from Ps_Job a 
      where a.empid = '101' 
      and a.emprcd ='#1' 
      and a.effdt = (select max(a1.effdt) from Psjob1)  where ... 
      and a.effseq = (Select  max(a2.effseq) from Ps_job2)
      where .....  )