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  • MYSQL多行合并成一行多列

    原数据:
    id      code           name            value
             -----------      ----------        --------  
    1      2014000          A                       10
    2      2014000          B                       9
    3      2014001          C                       100
    4      2014002          D                       4
    5      2014002          E                        5 
    6      2014003          F                       9
    7     2014003          G                      10 

    期望结果:
              code           name1            value1           name2            value2
             -----------       ---------              ---------          ---------              ---------   
             2014000          A                      10                   B                   9
             2014001          C                     100               null               null                                         
             2014002         D                       4                   E                     5
             2014003         F                       9                   G                   10



    注意:同1个ID最多只2条记录,会出现相同value。



    CREATE
    TABLE # (ID INT, code INT, NAME CHAR(1), VALUE VARCHAR(10)) INSERT INTO # VALUES (1,2014000,'A','10'), (2,2014000,'B','9'), (3,2014001,'C','100'), (4,2014002,'D','4'), (5,2014002,'E','5'), (6,2014003,'F','9'), (7,2014003,'G','10') SELECT code,MIN(name) AS name1,MIN(CAST(REPLACE(value,' ','') AS INT)) AS value1, CASE COUNT(ID) WHEN 1 THEN NULL ELSE MAX(name) END AS name2, CASE COUNT(ID) WHEN 1 THEN NULL ELSE MAX(CAST(REPLACE(value,' ','') AS INT)) END AS value2 FROM # GROUP BY code
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  • 原文地址:https://www.cnblogs.com/onetwo/p/6393826.html
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