Question

我试图得到两个计数，然后将这两个计数除以得到我计算的项目的比率。我看到了这篇文章here并试了一下。我的结果中出现错误，没有错误消息只是错误的数字。我正在使用SQL-Server 2008

这是我的代码：

-- INTERNAL PEPPER REPORT
--#####################################################################

-- VARIABLE DECLARATION AND INITIALIZATION
DECLARE @SD DATETIME
DECLARE @ED DATETIME

SET @SD = '2013-01-01'
SET @ED = '2013-03-31'

-- TABLE DECLARATION ##################################################
DECLARE @TABLE1 TABLE(NUMERATOR INT, DENOMINATOR INT, RATIO INT)
--#####################################################################

-- WHAT GETS INSERTED INTO TABLE 1
INSERT INTO @TABLE1
SELECT
A.NUM, A.DENOM, A.NUM/A.DENOM 

FROM
(
-- COLUMN SELECTION. TWO NUMBERS WILL REPRESENT A NUM AND A DENOM
SELECT 
    (SELECT COUNT(DRG_NO)
        FROM smsdss.BMH_PLM_PtAcct_V
        WHERE drg_no IN (061,062,063,064,065,066)
        AND Adm_Date BETWEEN @SD AND @ED
        AND PLM_PT_ACCT_TYPE = 'I')
        AS NUM,
    (SELECT COUNT(DRG_NO)
        FROM smsdss.BMH_PLM_PtAcct_V
        WHERE drg_no IN (061,062,063,064,065,066,067,068,069)
        AND Adm_Date BETWEEN @SD AND @ED
        AND Plm_Pt_Acct_Type = 'I')
        AS DENOM
)A

SELECT NUMERATOR, DENOMINATOR, RATIO
FROM @TABLE1

计数产生并正确显示，但是对于一个比例，我得到0并且不确定为什么我得到它。

谢谢，

Answer 1

使用SELECT A.NUM, A.DENOM, cast(A.NUM as float)/cast(A.DENOM as float)

SQL Server认为A.NUM / A.DENOM在，因为A.NUMBER和A.NUM是int

Answer 2

您的查询结构困扰我。你可以更有效地做到：

SELECT A.NUMer, A.DENOM, cast(A.NUMer as float)/A.DENOM 
FROM (SELECT COUNT(case when drg_no IN (061,062,063,064,065,066) then DRG_NO
                   end ) as Numer,
             count(case when drg_no IN 061,062,063,064,065,066,067,068,069) then DRG_NO
                   end) as denom
      FROM smsdss.BMH_PLM_PtAcct_V
      WHERE drg_no IN (061,062,063,064,065,066)
        AND Adm_Date BETWEEN @SD AND @ED
        AND PLM_PT_ACCT_TYPE = 'I'
     ) a

这不会影响整数除法问题，但原始查询过于复杂。

Answer 3

两个整数的比率是整数。例如：10/20 = 0.5 = 0.您需要将比率转换为浮点数才能得到准确答案。

Answer 4

由于整数除法而截断。你可以通过施法来定期进行分割。

INSERT INTO @TABLE1
SELECT
A.NUM, A.DENOM, CAST(A.NUM AS FLOAT)/A.DENOM

Answer 5

改为在下面的查询中使用

SELECT
A.NUM, A.DENOM, cast(A.NUM as float)/cast(A.DENOM as float)

FROM
(
-- COLUMN SELECTION. TWO NUMBERS WILL REPRESENT A NUM AND A DENOM
SELECT 
    (SELECT COUNT(DRG_NO)
        FROM smsdss.BMH_PLM_PtAcct_V
        WHERE drg_no IN (061,062,063,064,065,066)
        AND Adm_Date BETWEEN @SD AND @ED
        AND PLM_PT_ACCT_TYPE = 'I')
        AS NUM,
    (SELECT COUNT(DRG_NO)
        FROM smsdss.BMH_PLM_PtAcct_V
        WHERE drg_no IN (061,062,063,064,065,066,067,068,069)
        AND Adm_Date BETWEEN @SD AND @ED
        AND Plm_Pt_Acct_Type = 'I')
        AS DENOM
)A

问题是，如果num和denom都为INT，则除法也会返回INT，因此将其中一个（或两个）转换为float会导致float为除法结果

获得两个计数，然后将它们分开

5 个答案: