Tsql IF…CASE返回语法错误

在寻找错误方面投入了大量时间。我使用了另外两个工作函数作为构建此函数的指南，但遗憾的是，到目前为止，我还是失败了。有人能告诉我为什么返回语法错误：

FUNCTION FN_USER_MATRIX_PriceTweak 
(
@Cost float, @CostAvg float, 
@Tier1MaxVal float, @Tier1Mult float,
@Tier2MaxVal float, @Tier2Mult float, 
@Tier3MaxVal float, @Tier3Mult float,
@Tier4MaxVal float, @Tier4Mult float, 
@Tier5MaxVal float, @Tier5Mult float, 
@Above5Mult float
)
RETURNS float
AS
BEGIN

DECLARE @Result float

SET @Result = 
(
IF @Cost <= @CostAvg
    CASE
        WHEN @Cost <= @Tier1MaxVal THEN @Cost * @Tier1Mult
        WHEN @Cost <= @Tier2MaxVal THEN @Cost * @Tier2Mult
        WHEN @Cost <= @Tier3MaxVal THEN @Cost * @Tier3Mult
        WHEN @Cost <= @Tier4MaxVal THEN @Cost * @Tier4Mult
        WHEN @Cost <= @Tier5MaxVal THEN @Cost * @Tier5Mult
        ELSE @Cost * @Above5Mult
ELSE    
    CASE
        WHEN @CostAvg <= @Tier1MaxVal THEN @CostAvg * @Tier1Mult
        WHEN @CostAvg <= @Tier2MaxVal THEN @CostAvg * @Tier2Mult
        WHEN @CostAvg <= @Tier3MaxVal THEN @CostAvg * @Tier3Mult
        WHEN @CostAvg <= @Tier4MaxVal THEN @CostAvg * @Tier4Mult
        WHEN @CostAvg <= @Tier5MaxVal THEN @CostAvg * @Tier5Mult
        ELSE @CostAvg * @Above5Mult
)       

RETURN @Result
END

函数FN\u用户\u矩阵\u价格调整
(
@成本浮动，@CostAvg浮动，
@Tier1最大浮动，@Tier1多浮动，
@Tier2MaxVal浮点，@Tier2Mult浮点，
@Tier3MaxVal浮点，@Tier3Mult浮点，
@Tier4MaxVal浮动、@Tier4Mult浮动、，
@Tier5MaxVal浮点，@Tier5Mult浮点，
@5个以上浮点数
)
返回浮动
作为
开始
声明@Result float
设置@Result=
(
如果@Cost您应该使用嵌套的
案例
，其中包含您的
IF…ELSE
：

SET @Result = 
(
CASE WHEN @Cost <= @CostAvg THEN (
    CASE
        WHEN @Cost <= @Tier1MaxVal THEN @Cost * @Tier1Mult
        WHEN @Cost <= @Tier2MaxVal THEN @Cost * @Tier2Mult
        WHEN @Cost <= @Tier3MaxVal THEN @Cost * @Tier3Mult
        WHEN @Cost <= @Tier4MaxVal THEN @Cost * @Tier4Mult
        WHEN @Cost <= @Tier5MaxVal THEN @Cost * @Tier5Mult
        ELSE @Cost * @Above5Mult END)
ELSE    
    (CASE
        WHEN @CostAvg <= @Tier1MaxVal THEN @CostAvg * @Tier1Mult
        WHEN @CostAvg <= @Tier2MaxVal THEN @CostAvg * @Tier2Mult
        WHEN @CostAvg <= @Tier3MaxVal THEN @CostAvg * @Tier3Mult
        WHEN @CostAvg <= @Tier4MaxVal THEN @CostAvg * @Tier4Mult
        WHEN @CostAvg <= @Tier5MaxVal THEN @CostAvg * @Tier5Mult
        ELSE @CostAvg * @Above5Mult END)
END
)

SET@Result=
(
当@Cost时，请尝试以下方法：

IF @Cost <= @CostAvg
BEGIN
    SET @Result =  CASE
        WHEN @Cost <= @Tier1MaxVal THEN @Cost * @Tier1Mult
        WHEN @Cost <= @Tier2MaxVal THEN @Cost * @Tier2Mult
        WHEN @Cost <= @Tier3MaxVal THEN @Cost * @Tier3Mult
        WHEN @Cost <= @Tier4MaxVal THEN @Cost * @Tier4Mult
        WHEN @Cost <= @Tier5MaxVal THEN @Cost * @Tier5Mult
        ELSE @Cost * @Above5Mult
    END
END
ELSE  
BEGIN
    SET @Result =  CASE
        WHEN @CostAvg <= @Tier1MaxVal THEN @CostAvg * @Tier1Mult
        WHEN @CostAvg <= @Tier2MaxVal THEN @CostAvg * @Tier2Mult
        WHEN @CostAvg <= @Tier3MaxVal THEN @CostAvg * @Tier3Mult
        WHEN @CostAvg <= @Tier4MaxVal THEN @CostAvg * @Tier4Mult
        WHEN @CostAvg <= @Tier5MaxVal THEN @CostAvg * @Tier5Mult
        ELSE @CostAvg * @Above5Mult
    END
END

RETURN @Result

IF@Cost您没有正确地使用IF语句。您应该使用嵌套的CASE语句，而不是相反。结果发现有两个问题没有在初始响应（或帮助菜单）中完全解释：我的CASE语句需要一个END语句，这是我不知道的要求。其次，SET的右侧不能以IF语句开头。