多行查询结果合并成一个

准备数据：

CREATE TABLE TEST_GROUP_A (

  STDCODE VARCHAR2(30),

  DEMO VARCHAR2(100)

);

insert into TEST_GROUP_A values ('1001','AAA');

insert into TEST_GROUP_A values ('1001','BBB');

insert into TEST_GROUP_A values ('1002','CCC');

insert into TEST_GROUP_A values ('1001','AGE');

 


查询实现:

       Oracle数据库：

            SELECT STDCODE, WMSYS.WM_CONCAT(DEMO)

              FROM TEST_GROUP_A T

             WHERE 1 = 1

             GROUP BY STDCODE



      MySQL数据库：

            SELECT STDCODE, GROUP_CONCAT(DEMO)

              FROM TEST_GROUP_A T

             WHERE 1 = 1

             GROUP BY STDCODE