存储过程逻辑错误

Question

我正在尝试做类似的事情 我该如何改进这个SQL查询？

但是,在那里逻辑基本上我有一个ID列表,可能有多个与之关联的值,值为Yes,No或其他字符串.对于ID x,如果任何值为Yes,则x应为Yes,如果它们都为No,则它应为No,如果它们包含任何其他值但是yes和no,则显示该值.我只想每个ID返回1行,没有重复.

但是在我的逻辑中如果所有值都是肯定的,那么显示是,如果所有值都是否则显示否,如果它是是,否或其他任何显示组合的混合

DECLARE @tempTable table ( ID int, Val varchar(1) )

    INSERT INTO @tempTable ( ID, Val ) VALUES ( 10, 'Y')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 11, 'N')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 11, 'N')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 12, 'Y')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 12, 'Y')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 12, 'Y')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 13, 'N')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 14, 'Y')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 14, 'N')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 15, 'Y')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 16, 'Y')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 17, 'F')
    INSERT INTO @tempTable ( ID, Val ) VALUES ( 18, 'P')


    SELECT DISTINCT t.ID, COALESCE(t2.Val, t3.Val, t4.Val)
    FROM @tempTable t
    LEFT JOIN
    (
        SELECT ID, Val
        FROM @tempTable
        WHERE Val = 'Y'
    ) t2 ON t.ID = t2.ID
    LEFT JOIN
    (
        SELECT 
        ID, Val FROM @tempTable
        WHERE Val = 'N'
    ) t3 ON t.ID = t3.ID
    LEFT JOIN
    (
        SELECT ID, Val
        FROM @tempTable
        WHERE Val <> 'Y' AND Val <> 'N'
    ) t4 ON t.ID = t4.ID

Update dbo.households
SET dbo.households.code = #TempTable.code
FROM #TempTable
WHERE dbo.households.id = #TempTable.id 

Answer 1

SELECT  ID ,
        CASE WHEN MAX(Val) = MIN(Val)
                  AND MAX(Val) IN ( 'N', 'Y' ) THEN MAX(Val)
             ELSE 'M'
        END
FROM    @tempTable
GROUP BY ID

或者返回的版本Y,如果任何存在,而不是如果一切都Y

SELECT  ID ,
        ISNULL(MAX(CASE WHEN Val = 'Y' THEN 'Y' END), 
               CASE WHEN MAX(Val) = MIN(Val) THEN MAX(Val)
                              ELSE 'M'
                         END)
FROM    @tempTable
GROUP BY ID

或者最终版本,字面意思是"如果它们包含任何其他值,但是是和否,则显示该值." 声明.

SELECT  ID ,
        ISNULL(MAX(CASE WHEN Val = 'Y' THEN 'Y'END), 
               ISNULL(MAX(CASE WHEN Val NOT IN ( 'N', 'Y' ) THEN Val END), 
                      MAX(Val)))
FROM    @tempTable
GROUP BY ID