Question

我需要以下示例的帮助，这个例子是连接4个表和左外连接的结果，因为我需要检查所有列甚至知道可以获得空值，但我真正想要的是得到1根据c6上的最后一个更高值记录每个C6。

C1  C2  C3  C4  C5  C6
4   A   MM  90  GT  798
4   A   MM  90  GT  625
4   A   MM  90  GT  354
4   A   MM  90  GT  547
5   K   EE  60  SV  213
5   K   EE  60  SV  235
5   K   EE  60  SV  236
9   O   WW  40  PE  456
9   O   WW  40  PE  487
9   O   WW  40  PE  982

我正在使用的查询是这样的：

＆＃13;

SELECT distinct   C1, C2, C3, C4,C5,C6
	  --,row_number() OVER(partition by c6 ORDER BY c1 asc)    	  
  FROM table1 n
  left outer join  table 2 j on j.cad = n.Cad and j.P = n.P and j.H = 'Name'
  left outer join  table 3 k on k.id = n.id
  left outer join  table 4 m on m.u = n.u and m.s = n.s and m.Cad = n.Cad  and n.P = m.P
where NOT EXISTS   (SELECT 1 from table 5 v WHERE N.U=v.U and N.S=v.S 
                       and N.Cad=v.Cad and N.P=v.P) and n.Cad is not null
					   and C6 is not null

＆＃13;

Answer 1

尝试使用以下查询。

   With cte_1
     As(   SELECT C1, C2, C3, C4,C5,C6
      ,row_number() OVER(partition by c1,c2,c3,c4,c5    ORDER BY c6 desc)   RNO  
      FROM table1 n
         left outer join  table 2 j on j.cad = n.Cad and j.P = n.P and j.H = 'Name'
         left outer join  table 3 k on k.id = n.id
         left outer join  table 4 m on m.u = n.u and m.s = n.s and m.Cad = n.Cad  and n.P = m.P
        where NOT EXISTS   (SELECT 1 from table 5 v      WHERE N.U=v.U and N.S=v.S 
                       and N.Cad=v.Cad and N.P=v.P) and n.Cad is not null
                       and C6 is not null)

       SELECT C1, C2, C3, C4,C5,C6 FROM cte_1
      WHERE RNO=1

根据另一列上的最后一个唯一值选择1条记录

1 个答案: