Case语句中的SQL除以零错误和语法错误

Question

我正在用SQL生成报告。 我的错误除以零。 为了解决此错误，我在SQL查询中使用了大小写。 现在我在'as'处收到语法错误。 有谁可以帮助我解决此问题？

create procedure dbo.CompanyAverageSales @startdate as varchar(50),@enddate 
as varchar(50)
As begin

select  datename(year,SO_SalesOrder.InvoicedDate) as [Year],
    datename(month,SO_SalesOrder.InvoicedDate) as [Month],
    l.Name as [Store Name], 
    case when sum(convert(int,SO_SalesOrder.Custom1))>0 then sum(SO_SalesOrder_Line.SubTotal)/sum(convert(int,SO_SalesOrder.Custom1)) as [Average Sales]
From SO_SalesOrder
inner join BASE_Location l on SO_SalesOrder.LocationId = l.LocationId 
inner join SO_SalesOrder_Line
on SO_SalesOrder.SalesOrderId = SO_SalesOrder_Line.SalesOrderId
inner join BASE_PaymentTerms
on BASE_PaymentTerms.PaymentTermsId = SO_SalesOrder.PaymentTermsId
where SO_SalesOrder.InvoicedDate >= @startdate and SO_SalesOrder.InvoicedDate <= @enddate
group by l.Name,
         datename(year,SO_SalesOrder.InvoicedDate),
         datename(month,SO_SalesOrder.InvoicedDate)


end

Answer 1

在AS之前添加END

case 
when sum(convert(int,SO_SalesOrder.Custom1))>0 
then 
    sum(SO_SalesOrder_Line.SubTotal)/sum(convert(int,SO_SalesOrder.Custom1)) 
Else 
    0
END as [Average Sales]

Answer 2

case when sum(convert(int,SO_SalesOrder.Custom1))>0 then 
sum(SO_SalesOrder_Line.SubTotal)/sum(convert(int,SO_SalesOrder.Custom1)) as 
[Average Sales

应该：

 case when sum(convert(int,SO_SalesOrder.Custom1))>0 then 
 sum(SO_SalesOrder_Line.SubTotal)/sum(convert(int,SO_SalesOrder.Custom1)) 
 ELSE 0 -- your logic here
 END as [Average Sales

Answer 3

在这种情况下，避免被零除的一个好方法是使用NULLIF ：

sum(SO_SalesOrder_Line.SubTotal) 
/ 
NULLIF(sum(convert(int,SO_SalesOrder.Custom1)), 0)

如果sum(convert(int,SO_SalesOrder.Custom1)) = 0则返回NULL

如果要返回0则可以将表达式包装在COALESCE ：

COALESCE(sum(SO_SalesOrder_Line.SubTotal) 
         / 
         NULLIF(sum(convert(int,SO_SalesOrder.Custom1)), 0), 0)

Answer 4

select
    sum(SO_SalesOrder_Line.SubTotal)/NULLIF(sum(convert(int,SO_SalesOrder.Custom1)),0)
FROM ...

对于结果除以零的记录，这将返回Null。

Answer 5

这行会产生错误：

case when sum(convert(int,SO_SalesOrder.Custom1))>0 then sum(SO_SalesOrder_Line.SubTotal)/sum(convert(int,SO_SalesOrder.Custom1)) as [Average Sales]

您应该以end case陈述：

case when sum(convert(int,SO_SalesOrder.Custom1))>0 then sum(SO_SalesOrder_Line.SubTotal)/sum(convert(int,SO_SalesOrder.Custom1)) end as [Average Sales]