MYSQL多行合并成一行多列

时间:2021-10-06 10:28:54
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