如果不考虑效率问题with t1 as ( select 1 c1,'a' c2 from dual union all select 2 c1,'b' c2 from dual union all select 3 c1,'c' c2 from dual union all select 4 c1,'d' c2 from dual )select a.c2||b.c2 c1 from t1 a full join t1 b on a.c2 < b.c2 where length(a.c2||b.c2) > length(a.c2) c1 ------------------ 1 ab 2 ac 3 ad 4 bc 5 bd 6 cd
with t1 as ( select 1 c1,'a' c2 from dual union all select 2 c1,'b' c2 from dual union all select 3 c1,'c' c2 from dual union all select 4 c1,'d' c2 from dual )select wm_concat(a.c2||b.c2) c1 from t1 a join t1 b on a.c2 < b.c2刚看到一个函数,这样可以查到,感谢上面的提示
(
select 1 c1,'a' c2 from dual
union all
select 2 c1,'b' c2 from dual
union all
select 3 c1,'c' c2 from dual
union all
select 4 c1,'d' c2 from dual
)select a.c2||b.c2 c1
from t1 a full join t1 b on a.c2 < b.c2
where length(a.c2||b.c2) > length(a.c2) c1
------------------
1 ab
2 ac
3 ad
4 bc
5 bd
6 cd
(
select 1 c1,'a' c2 from dual
union all
select 2 c1,'b' c2 from dual
union all
select 3 c1,'c' c2 from dual
union all
select 4 c1,'d' c2 from dual
)select wm_concat(a.c2||b.c2) c1
from t1 a join t1 b on a.c2 < b.c2刚看到一个函数,这样可以查到,感谢上面的提示