wmsys.wm_concat详细示例.txt

wmsys.wm_concat: 连接多条记录的某一列，用逗号隔开。
concat(col1,col2) ：连接一条记录的两列
col1 || col2 || col3 ：连接记录的多列

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create table idtable (id number,name varchar2(30));
insert into idtable values(10,'ab');
insert into idtable values(10,'bc');
insert into idtable values(10,'cd');
insert into idtable values(20,'hi');
insert into idtable values(20,'ij');
insert into idtable values(20,'mn');

SQL> select * from idtable;

        ID NAME
---------- ------------------------------
        10 ab
        10 bc
        10 cd
        20 hi
        20 ij
        20 mn

SQL> select id,wmsys.wm_concat(name) name from idtable group by id;

        ID NAME
---------- --------------------------------------------------------------------------------