我自己写出来了,不知效率如何
select DBMS_RANDOM.RANDOM,c.id ,wmsys.wm_concat(c.name) end from
(
select rownum as id, a.name from tab_a a where rownum<5
union all
select rownum as id,b.name from tab_b b where rownum<5
) c
group by c.id
select DBMS_RANDOM.RANDOM,c.id ,wmsys.wm_concat(c.name) end from
(
select rownum as id, a.name from tab_a a where rownum<5
union all
select rownum as id,b.name from tab_b b where rownum<5
) c
group by c.id
解决方案 »
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select a.id,a.name||b.name from tab_a a,tab_b b where a.id=b.id order by 1
select t1.rn, t1.name || t2.name
from (select rownum rn, t1.name from t1 where rownum < 5) t1,
(select rownum rn, t2.name from t2 where rownum < 5) t2
where t1.rn = t2.rn
select t1.rn, t1.name || t2.name
from (select rownum rn, t1.name from t1 where rownum < 5) t1,
(select rownum rn, t2.name from t2 where rownum < 5) t2
where t1.rn = t2.rn额 楼主说了 表没有关联的、
select t1.rn, t1.name || t2.name
from (select rownum rn, t1.name from t1 where rownum < 5) t1,
(select rownum rn, t2.name from t2 where rownum < 5) t2
where t1.rn = t2.rn额 楼主说了 表没有关联的、自己查个行号当关联,多套一层而已。
两个表join下,合并字符串就好
select t1.rn, t1.name || t2.name
from (select rownum rn, t1.name from t1 where rownum < 5) t1,
(select rownum rn, t2.name from t2 where rownum < 5) t2
where t1.rn = t2.rn
为什么要写的这么麻烦啊
这样:
select t1.no, t1.name||t2.name from t1,t2 where t1.no=t2.no;不是很简单吗
SELECT A.ID,A.NAME||B.NAME AS NAME FROM T_A A JOIN T_B B ON A.ID=B.IDok