Question

我有一些代码用于计算表中行的平均值。问题是，MinTwee，MinEen，nul，PlusEen和PlusTwee （列名称）的总和是等于零，它给我一个除零异常（当然是正常的）。你怎么能保护它不给它呢？我想如果总和等于零，那么平均值也等于该行的零。我使用的是SQL Server 2014。

select top 5 
    id, mintwee, mineen, nul, pluseen, plustwee, naam
from 
    topic 
where 
    CategorieID = 7 and verwijderd = 0 
order by 
    round(cast((mintwee * (-2) + mineen * (-1) + nul * 0 + pluseen * 1 + PlusTwee * 2) as float) / (MinTwee + MinEen + nul + PlusEen + PlusTwee), 1) desc, creatie desc

Answer 1

您可以使用

时的情况测试0值

select top 5 id, mintwee, mineen, nul, pluseen, plustwee, naam
from topic 
where CategorieID = 7 and verwijderd = 0 
order by 
   case when (MinTwee + MinEen + nul + PlusEen + PlusTwee) = 0 then  creatie
   else
   round(cast((mintwee * (-2) + mineen * (-1) + nul * 0 + pluseen * 1 + PlusTwee * 2) as float) / (MinTwee + MinEen + nul + PlusEen + PlusTwee), 1)
   end
    desc, 
   creatie desc

Answer 2

我认为避免错误的最简单方法是nullif()：

order by 
    coalesce(round(cast((mintwee * (-2) + mineen * (-1) + nul * 0 + pluseen * 1 + PlusTwee * 2) as float) /
          nullif(MinTwee + MinEen + nul + PlusEen + PlusTwee, 0), 1), 0) desc,
    creatie desc

除以SQL Server中一行中列的平均值的异常

2 个答案: