sql-server - case 表达式只显示一次

Question

我有一个遇到困难的案例表达：

WHEN @CustomerID = 3 AND @OrderID = 2 AND @Name IN ('Hello') THEN 'Regular'
WHEN @CustomerID = 3 AND @OrderID = 2 AND @Telephone = 1 AND @Name IN ('Hello') THEN 'Business'

如果我有两个语句，它只会返回“常规”，但如果我取出“常规”，它会显示商业语句。我究竟做错了什么？

标签： sql-server

Answer 1

如果您想要其中一个或两个，则它需要是两个单独的列，或者如果您想要一个列，则在其中包含两个输出：

任何一个：

case WHEN @CustomerID = 3 AND @OrderID = 2 AND @Name IN ('Hello') THEN 'Regular' end,
case WHEN @CustomerID = 3 AND @OrderID = 2 AND @Telephone = 1 AND @Name IN ('Hello') THEN 'Business' end

或者：

WHEN @CustomerID = 3 AND @OrderID = 2 AND @Telephone = 1 AND @Name IN ('Hello') THEN 'Regular, Business' 
WHEN @CustomerID = 3 AND @OrderID = 2 AND @Name IN ('Hello') THEN 'Regular'