每当我运行它时，我都有以下查询，它在'As'附近给出了错误的语法

Question

SELECT 
CAST((Discount_Amount AS numeric(11,2))/1.14)*0.14 AS [Service Tax]
FROM APDEPADV

Answer 1

我认为你的括号在错误的地方：

SELECT 
(CAST(Discount_Amount AS numeric(11,2))/1.14)*0.14 AS [Service Tax]
FROM APDEPADV

您应首先投射Discount_Amount，然后执行其他计算：

1. 将Discount_Amount转换为数值
2. 接下来，将结果除以1.14
3. 最后，将它全部乘以0.14

如果你稍微破解你的代码，你可能会理解发生了什么：

1. CAST具有以下语法：CAST(a AS b)
2. 您的代码有：CAST((Discount_Amount AS numeric(11,2))/1.14)
3. 因为你的内部 CAST函数，所以整个表达式(Discount_Amount AS numeric(11,2))/1.14被视为你想要投射的值（a 1以上）。

这会产生一些后果。首先，CAST(a AS b)现在变为CAST(a)，这没有多大意义（你将它投射到什么地方？）

其次，这意味着表达式Discount_Amount AS numeric(11,2)正在与CAST函数分开处理。像Discount_Amount/1.14这样的东西是一个有效的表达式，但(Discount_Amount AS numeric(11,2))/1.14本身不是，这就是你收到错误的原因。

通过重新排列括号，您应该更接近您的意图：

SELECT
(
    CAST(Discount_Amount AS numeric(11,2))
    /1.14
)
* 0.14
AS [Service Tax]
FROM APDEPADV

Answer 2

试试这个

 SELECT 
    (CAST(Discount_Amount AS numeric(11,2))/1.14)*0.14 AS [Service Tax]
    FROM APDEPADV

Answer 3

括号的顺序是错误的。理解表达式，然后相应地重写括号。

SELECT
((Cast(Discount_Amount AS numeric(11,2))/1.14)*0.14 AS [Service Tax]
FROM APDEPADV