SQL 四舍五入似乎没有按预期工作

Question

我有以下 SQL 查询。

      DECLARE
     @StartDate  DATE ='20160101' ,
  @EndDate  DATE = '20160331', 

  @Box1  DECIMAL,
  @Box2  DECIMAL,
  @Box3  DECIMAL,
  @Box4  DECIMAL,
  @Box5  DECIMAL,
  @Box6  DECIMAL,
  @Box7  DECIMAL,
  @Box8  DECIMAL,
  @Box9  DECIMAL


SET @Box1 = (SELECT ROUND(SUM (vt.Vat),2) FROM VatTransactions vt WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

SET @Box2 = (SELECT ROUND(SUM(vt.VatDueOnECPurchases/vt.ConversionFactor),2) FROM VatTransactions vt WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

SET @Box3 = (SELECT ROUND(SUM(@Box1 + @Box2),2))

SET @Box4 = (SELECT (ROUND(SUM(vt.VatInput),2) + @Box2) FROM VatTransactions vt WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

SET @Box5 =(SELECT @Box3 - @Box4)

SET @Box8 = (SELECT ROUND(SUM(vt.SlAway/vt.ConversionFactor),2) FROM VatTransactions vt WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

SET @Box9 = (SELECT ROUND(SUM(vt.PlAway/vt.ConversionFactor),2) FROM VatTransactions vt  WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

SET @Box6 = (SELECT (ROUND(SUM(vt.SlHome),2) + @Box8) FROM VatTransactions vt WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

SET @Box7 = (SELECT (ROUND(SUM(vt.PlHome),2) + @Box9) FROM VatTransactions vt WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

SELECT @Box1 AS BOX1, @Box2 AS Box2, @Box3 AS Box3, @Box4 AS Box4, @Box5 AS Box5, @Box6 AS Box6, @Box7 AS Box7, @Box8 AS Box8, @Box9 AS Box9

当这是运行时，它会产生以下结果；

查询从中获取信息的表中的所有字段（日期明显除外）都定义为货币或小数类型。

实际上Box4的数字应该是1351.17，box5的数字应该是-1351.17

为什么我会看到上面的结果，我应该怎么做才能得到我期望的结果？

Answer 1

@Box4  DECIMAL
       ^^^  here is your problem

您的 DECIMAL 类型从来没有超过小数点的任何精度。因此，SQL 服务器显示小数点后精度为零位的值，即整数。

由于您似乎需要两位小数的精度，请尝试使用此声明：

@Box4  DECIMAL(10,2)

Answer 2

能否请您尝试以下

SET @Box4 = (SELECT (ROUND(SUM(vt.VatInput * 1.0),2) + @Box2) FROM VatTransactions vt WHERE vt.VatTransactionDate BETWEEN @StartDate AND @EndDate)

您会注意到我将列值乘以十进制数 1.0 这会将结果转换为十进制数否则，如果 VatInput 是整数计算，它将是 integer

SQL 四舍五入似乎没有按预期工作

SQL rounding does not appear to work as expected

sql

sql-server-2014-express