Oracle中字符串连接

表：b_Atest

create table b_Atest
(
 testA int,
 testB nvarchar2(100),
 testC nvarchar2(100)
)

表：b_Btest

create table b_Btest
(
 textA int ,
 testA int ,
 textC nvarchar2(100),
 textD nvarchar2(100)
)

数据源：

select * from b_Atest
insert into b_Atest(testA,testB,testC) values(1,'B1','C1');
insert into b_Atest(testA,testB,testC) values(2,'B2','C2');
insert into b_Atest(testA,testB,testC) values(3,'B3','C3');
insert into b_Atest(testA,testB,testC) values(4,'B4','C4');
insert into b_Atest(testA,testB,testC) values(5,'B5','C5');
select * from b_Btest
insert into b_Btest(textA,testA,textC,textD) values(7,3,'G1','G2');
insert into b_Btest(textA,testA,textC,textD) values(8,3,'G3','G4');
insert into b_Btest(textA,testA,textC,textD) values(6,3,'G5','G5');

执行语句：select * from b_Atest  a  left join b_Btest b on a.testa = b.testa

执行语句：

select max(a.testa) as testa,
       max(a.testb) as testb,
       max(a.testc) as testc,
       wmsys.wm_concat(to_char(a.testb) || '-' || to_char(a.testc)  || '-' || to_char(b.textc)  || '-' || to_char(b.textd)  || CHR(10))
from b_Atest  a
left join b_Btest b on a.testa = b.testa
group by a.testa