无法将值写入变量

Question

我有一个函数，如果表中有一行包含用户输入的值，则需要返回true。

我需要将值写入Ii返回的变量，但出现错误：

'@ ret'附近的语法不正确。

USE BDLab5;
GO
Create Function WasComplaint (@date date, @component varchar)
    Returns BIT
    Begin
        Declare @was int, @ret bit
        Select @was = ComponentCode from Complaints 
            Where ComplaintDate = @date AND 
            ComponentCode = (Select ComponentCode from Components Where ComponentName = @component)

        if (@was = 0)  
            @ret = 0
        else 
            @ret = 1 

        Return @ret
    End;

我尝试了if else语法的其他变体，但没有帮助。

Answer 1

将值分配给变量时，需要使用SET。

USE BDLab5;
GO
Create Function WasComplaint (@date date, @component varchar)
    Returns BIT
    Begin
        Declare @was int, @ret bit
        Select @was = ComponentCode from Complaints 
            Where ComplaintDate = @date AND 
            ComponentCode = (Select ComponentCode from Components Where ComponentName = @component)

        if (@was = 0)  
            set @ret = 0
        else 
            set @ret = 1 

        Return @ret
    End;

Answer 2

[在给SET值时将其放在@ret之前