select * from (select a.item,a.value,b.value from a,b where a.item=b.item and a.value<b.value order by a.item,a.value,b.value) where rownum<2
select * from (select t1.item a ,t1.value b ,t2.value c from t1 ,t2 where t1.item=t2.item and t2.value>t1.value)t where t.c=(select min(t.c) from (select t2.value from t1 ,t2 where t1.item=t2.item and t2.value>t1.value)t)
select 表1.item,表1.u_value,min(表2.u_value) from 表1,表2 where 表1.item=表2.item and 表2.u_value>=表1.u_value group by 表1.item,表1.u_value;
from a,b where a.item=b.item and a.value<b.value
order by a.item,a.value,b.value) where rownum<2
from 表1,表2
where 表1.item=表2.item and 表2.u_value>=表1.u_value
group by 表1.item,表1.u_value;