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 »
- 一个非常奇怪的ORACLE 读取问题?
- 如何用游标作参数
- 请教关于 控制台 Enterprise Manager Console 的一些问题 大家快来呀
- 用IMP导入DMP文件,到导入某一个表时不再有响应,CPU消耗70%以上,内存消耗50%以上,是什么原因?
- 求一个存储过程的写法
- 在 Oracle 中怎样实现自动编号?
- 执行程序,连接ORACLE时总提示丢包!
- oracle9i的date数据格式问题求救!
- 请教一个关于数据倒出的问题!
- 我从Oracle Enterprise Manager登录时,对话框中的Service填什么内容?多谢!
- 存储过程动态拼接sql过长,报ora-00604,ora-01003 如何解决
- group by后提取数据问题
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