SQL查询oracle返回超过预期的结果

Question

我有一个查询来获取一些数据：

select max(v.SEQUENCENO) as vmaxseq, v.CODE, v.NAMECODE, v.CODENO from smalltbl v join 
(select max(SEQUENCENO) as maxseq, CODE, CODENO from smalltbl group by CODE, CODENO) sm
on sm.CODE = v.CODE and sm.CODE = 'D50451489'
group by v.CODE, v.NAMECODE, v.CODENO;

但是当我跑步时，它会返回比我预期更多的数据：

我想要的只是在每个CODENO上返回VMAXSEQ的最大值，如下所示：

如何编写查询以仅获取这2个数据？

谢谢！

Answer 1

您可以使用分析功能执行所需操作。我认为你想要的查询是：

select sm.*
from (select sm.*, max(SEQUENCENO) over (partition by codeno) as maxseq
      from smalltbl sm
      where sm.CODE = 'D50451489'
     ) sm
where sequenceno = maxseq;

Answer 2

namecode是你的问题。因为它与你的行不同而且与codeno没有直接关系，所以你基本上都会得到一个笛卡尔积。

Answer 3

可能是这样的东西

SELECT T.*
FROM smalltbl T INNER JOIN
     (
      SELECT codeno,Max(SEQUENCENO) As vmaxseq
      FROM smalltbl where CODE = 'D50451489'
      GROUP BY codeno
     ) T1 ON T.SEQUENCENO = T1.vmaxseq AND T.codeno = T1.codeno

Answer 4

试试这个

select 
    vmaxseq, CODE, NAMECODE, CODENO
FROM (
    select 
        vmaxseq, CODE, NAMECODE, CODENO,
        FIRST_VALUE(vmaxseq) OVER (ORDER BY vmaxseq DESC) as firstmax   
        from (  
            select 
                max(v.SEQUENCENO) as vmaxseq, 
                v.CODE, 
                v.NAMECODE, 
                v.CODENO,               
            from smalltbl v 
                join (select max(SEQUENCENO) as maxseq, CODE, CODENO from smalltbl group by CODE, CODENO) sm
                    on sm.CODE = v.CODE and sm.CODE = 'D50451489'
        group by v.CODE, v.NAMECODE, v.CODENO
    ) 
) where firstmax = vmaxseq