Question

我有一个数据集（SQL Server 2012）我试图从每个帐号中提取最终的月度总数，并将不同的位置汇总在一起。我需要YYYYMMDD中月末最后一天的最终余额编号。拉入最小值或最大值不会起作用，因为余额可能更高或更低，但它需要Group By功能的聚合。你怎么能参考这个余额？

请参阅下面的示例，目标输出低于

Account#    Location    Balance    YYYYMMDD   YYYYMM  
     1       South      $400       20171030   201710  
     1       South      $395       20171031   201710  
     1       South      $402       20171101   201711  
     1       South      $408       20171102   201711  
     1       North      $75        20171030   201710  
     1       North      $80        20171031   201710  
     1       North      $80        20171101   201711  
     1       North      $72        20171102   201711  
     2       South      $5,000     20171030   201710  
     2       South      $5,200     20171031   201710  
     2       South      $5,200     20171101   201711  
     2       South      $5,500     20171102   201711  
     2       North      $2,000     20171030   201710  
     2       North      $1,800     20171031   201710  
     2       North      $1,700     20171101   201711  
     2       North      $1,600     20171102   201711  


Account#    Balance    YYYYMM  
     1       $475      201710  
     1       $480      201711  
     2       $7,000    201710  
     2       $7,100    201711

谢谢！

Answer 1

row_number()是一种典型的方法：

select t.*
from (select account, yyyymm, yyyymmdd, sum(balance) as balance,
             row_number() over (partition by account, yyyymm order by yyyymmdd desc) as seqnum
      from t
      group by account, yyyymm, yyyymmdd
     ) t
where seqnum = 1;

从一列中检索值，最大值为另一列

1 个答案: