SUM某个字段结果，如果为Null时则用0插入 怎么显示字符转化为number有误？
EG：
UPDATE BatchTicketDetail SET BatchTicketDetail_Waste = (Select Case Sum(BatchDetailBad_Qty) When 'null ' Then '0 ' else Sum(BatchDetailBad_Qty) end AS wQty From BatchDetailBad

Thanks!!!

[解决办法]
--将 'null ' 改为null
UPDATE BatchTicketDetail SET BatchTicketDetail_Waste = (Select Case Sum(BatchDetailBad_Qty) When null Then '0 ' else Sum(BatchDetailBad_Qty) end AS wQty From BatchDetailBad

[解决办法]
自己解决．．呵呵！就是有点疑问，会用case　when　居然不会用ISNULL?没想到吧！