• 数据库表行转列,列转行终极方案


    --行转列问题
    --建立测试环境
    Create Table TEST
    (DATES Varchar(6),
     EMPNO Varchar(5),
     STYPE Varchar(1),
     AMOUNT Int)
    --插入数据
    Insert TEST Select '200605',  '02436',     'A',        5
    Union All Select '200605',  '02436',     'B',        3
    Union All Select '200605',  '02436',     'C',        3 
    Union All Select '200605',  '02436',     'D',        2
    Union All Select '200605',  '02436',     'E',        9
    Union All Select '200605',  '02436',     'F',        7
    Union All Select '200605',  '02436',     'G',        6
    Union All Select '200605',  '02438',     'A',        7
    Union All Select '200605',  '02438',     'B',        8
    Union All Select '200605',  '02438',     'C',        0 
    Union All Select '200605',  '02438',     'D',        3
    Union All Select '200605',  '02438',     'E',        4
    Union All Select '200605',  '02438',     'F',        5
    Union All Select '200605',  '02438',     'G',        1
    GO
    --测试
    --如果STYPE固定,可以这麼写
    Select 
    DATES,
    EMPNO,
    SUM(Case STYPE When 'A' Then AMOUNT Else 0 End) As A,
    SUM(Case STYPE When 'B' Then AMOUNT Else 0 End) As B,
    SUM(Case STYPE When 'C' Then AMOUNT Else 0 End) As C,
    SUM(Case STYPE When 'D' Then AMOUNT Else 0 End) As D,
    SUM(Case STYPE When 'E' Then AMOUNT Else 0 End) As E,
    SUM(Case STYPE When 'F' Then AMOUNT Else 0 End) As F,
    SUM(Case STYPE When 'G' Then AMOUNT Else 0 End) As G
    From TEST
    Group By DATES,EMPNO
    Order By DATES,EMPNO

    --如果STYPE不固定,用动态语句
    Declare @S Varchar(1000)
    Set @S=''
    Select @S=@S+',SUM(Case STYPE When '''+STYPE+''' Then AMOUNT Else 0 End) As '+STYPE From (Select Distinct STYPE From TEST) A Order By STYPE
    Set @S='Select DATES,EMPNO'+@S+' From TEST Group By DATES,EMPNO Order By DATES,EMPNO'
    EXEC(@S)
    GO
    --如果被转置的是数字类型的话,应用下列语句
    DECLARE @S VARCHAR(1000)
    SET @S='SELECT DATES,EMPNO '
    SELECT @S=@S+',['+STYPE+']=SUM(CASE WHEN STYPE='''+STYPE+''' THEN AMOUNT ELSE 0 END)'
    FROM (Select Distinct STYPE From TEST) A Order By STYPE
    SET @S=@S+' FROM TEST GROUP BY DATES,EMPNO'
    EXEC(@S) 

    如果是列转的话直接Union All就可以了

    例如 :

    city style      color 46 48 50 52
    长沙 S6MF01002   152  1  2  2 1
    长沙 S6MF01002   201  1  2  2 1
    上面到下面的样子
    city   style          color size qty
    长沙 S6MF01002       152    46  1
    长沙 S6MF01002       152    48   2
    长沙 S6MF01002       152    50   2
    长沙 S6MF01002       152    52  1
    长沙 S6MF01002       201    46  1
    长沙 S6MF01002       201    48  2
    长沙 S6MF01002       201    50  2
    长沙 S6MF01002       201    52  1

    Select City,Style,Color,[46] From Test
    Union all 
    Select City,Style,Color,[48] From Test
    Union all 
    Select City,Style,Color,[50] From Test
    Union all 
    Select City,Style,Color,[52] From Test

    就可以了

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  • 原文地址:https://www.cnblogs.com/daichangya/p/12959665.html
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