Sql server 若要在上的左连接后不为null，将删除由null扩展的任何行，即只在行上保留内部连接，即“将外部连接转换为内部连接”。始终知道作为左联接的一部分，您需要什么样的内部联接。@JasperS3000我无法获得参数1（值为0.5）的预期结果。使用您当前的数据和业

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若要在上的左连接后不为null，将删除由null扩展的任何行，即只在行上保留内部连接，即“将外部连接转换为内部连接”。始终知道作为左联接的一部分，您需要什么样的内部联接。@JasperS3000我无法获得参数1（值为0.5）的预期结果。使用您当前的数据和业务逻辑，您可以将记录分解为0.5吗？@EzLo输入参数1指示，在tblAnimals表中，只有总共有1个“怪癖”的行都被考虑了。这样的行有4行。那应该成为我们的分母。为了建立分子，我们现在查看tblJobEntries表，检查与分母中的行共享相同日期的行（刚刚建立的），并计算至少一个CASE语句产生大于0盈余的相同日期分子行的数量。有两行这样的行，所以我们剩下的分子是2，分母是4，十进制形式等于。5。浮点数据类型的更改非常重要。但是，您的Select语句产生错误的结果，因为根据我对该测试数据的手动计算，分母仍然没有拾取a.Quirks所期望的过滤器

Input Parameter       Correct Output Parameter
     0                       0
     1                      .5
     2                      .666
     3                      .666

--This is a user defined function containing 2 CTE's and a SELECT 
--statement with 2 joins and a WHERE clause. I included that structural 
--detail in case it makes a difference.


CREATE FUNCTION [dbo].[ExampleOfQueryStructure] 
(
    @MyInputParameter int
)
RETURNS 
@MyOutputParameter TABLE 
(
    [MyPercentage] float          
)
AS
BEGIN
WITH    Quirks_CTE (AnimalDateTime, Quirks) 
        AS   
           (SELECT 
               AnimalDateTime,
               (COALESCE (Lion, 0) + COALESCE (Zebra, 0) 
               + COALESCE (Antelope, 0) + COALESCE (Giraffe, 0)) 
           FROM dbo.tblAnimals),

        Surplus_CTE 
        AS
           (SELECT 
               JobEntryDateTime,
               CASE 
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel5-BeginLevel
                  ELSE BeginLevel-ExitLevel5
               END AS [5_SURPLUS],

               CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel8-BeginLevel
                  ELSE BeginLevel-ExitLevel8
               END AS [8_SURPLUS],

               CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel20-BeginLevel
                  ELSE BeginLevel-ExitLevel20
               END AS [20_SURPLUS],

               CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevelStone-BeginLevel
                  ELSE BeginLevel-ExitLevelStone
               END AS [StoneProfit]

        FROM dbo.tblJobEntries)


INSERT INTO @MyOutputParameter ([MyPercentage])
   SELECT 
       COUNT(a.Quirks)/COUNT(b.Quirks)
       FROM QuirksCTE b
       LEFT OUTER JOIN QuirksCTE a 
           ON b.AnimalDateTime = a.AnimalDateTime
              where exists(select 1 from Surplus_CTE c
                           where a.AnimalDateTime = c.JobEntryDateTime
                           AND ([5_SURPLUS] > 0 OR [8_SURPLUS] > 0 
                                OR [20_SURPLUS] > 0 OR [StoneProfit] > 0)   
                           AND a.Quirks <= @MyInputParameter)

RETURN
END

CREATE FUNCTION [dbo].[ExampleOfQueryStructure] 
(
    @MyInputParameter int
)
RETURNS 
@MyOutputParameter TABLE 
(
    [MyPercentage] float
)
AS
BEGIN
WITH    Quirks_CTE (AnimalDateTime, Quirks) 
        AS   
           (SELECT 
               AnimalDateTime,
               (COALESCE (Lion, 0) + COALESCE (Zebra, 0) 
               + COALESCE (Antelope, 0) + COALESCE (Giraffe, 0)) 
           FROM dbo.tblAnimals),

        Surplus_CTE 
        AS
           (SELECT 
               JobEntryDateTime,
               CASE 
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel5-BeginLevel
                  ELSE BeginLevel-ExitLevel5
               END AS [5_SURPLUS],

               CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel8-BeginLevel
                  ELSE BeginLevel-ExitLevel8
               END AS [8_SURPLUS],

               CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel20-BeginLevel
                  ELSE BeginLevel-ExitLevel20
               END AS [20_SURPLUS]
            FROM dbo.tblJobEntries)

INSERT INTO @MyOutputParameter ([MyPercentage])
   SELECT 
       COUNT(a.Quirks) * 1.0 /COUNT(b.Quirks)
       FROM Quirks_CTE b
       LEFT OUTER JOIN Quirks_CTE a 
           ON b.AnimalDateTime = a.AnimalDateTime
              AND exists(select 1 from Surplus_CTE c
                           where a.AnimalDateTime = c.JobEntryDateTime
                           AND ([5_SURPLUS] > 0 OR [8_SURPLUS] > 0 
                                OR [20_SURPLUS] > 0)   
                           AND a.Quirks <= @MyInputParameter)

RETURN
END

WITH    Quirks_CTE (AnimalDateTime, Quirks) 
        AS   
           (SELECT 
               AnimalDateTime,
               (COALESCE (Lion, 0) + COALESCE (Zebra, 0) 
               + COALESCE (Antelope, 0) + COALESCE (Giraffe, 0)) 
           FROM dbo.tblAnimals),

        Surplus_CTE 
        AS
           (SELECT 
               JobEntryDateTime,
               CASE 
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel5-BeginLevel
                  ELSE BeginLevel-ExitLevel5
               END AS [5_SURPLUS],

               CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel8-BeginLevel
                  ELSE BeginLevel-ExitLevel8
               END AS [8_SURPLUS],

               CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevel20-BeginLevel
                  ELSE BeginLevel-ExitLevel20
               END AS [20_SURPLUS],

              CASE
                  WHEN tblJobEntries.Stance = 1
                  THEN ExitLevelStone-BeginLevel
                  ELSE BeginLevel-ExitLevelStone
               END AS [StoneSurplus]            

            FROM dbo.tblJobEntries),
       AnimalSurplus AS
       (
         SELECT
           Q.AnimalDateTime,
           Q.Quirks,
           Surplus = CASE WHEN [5_SURPLUS] > 0 OR [8_SURPLUS] > 0 OR [20_SURPLUS] > 0 OR [StoneSurplus] > 0 THEN 1 END
         FROM
           Quirks_CTE AS Q
           LEFT JOIN Surplus_CTE AS S ON Q.AnimalDateTime = S.JobEntryDateTime
         )
   -- SELECT * FROM AnimalSurplus
   SELECT 
       COUNT(a.Quirks) * 1.0 /COUNT(b.Quirks)
       FROM AnimalSurplus b
       LEFT OUTER JOIN AnimalSurplus a 
           ON b.AnimalDateTime = a.AnimalDateTime AND a.Surplus = 1
       WHERE b.Quirks <= @MyInputParameter