Question

oracle 查询字段值重复sql语句

表 A 字段 b 想查询 b 字段有重复的数据。

Answer 1

你是要在一个查询里，一次查询出但凡是字段值重复的列，不知道我是否理解正确了。
select t.字段1,'' 字段2,...,'' 字段n
from t1 t
group by t.字段1
having count(t.字段1)>1
union all
select '' 字段1,t.字段2,...,'' 字段n
from t1 t
group by t.字段2
having count(t.字段2)>1
union all
...
union all
select '' 字段1,'' 字段2,...,t.字段n
from t1 t
group by t.字段n
having count(t.字段n)>1;

Answer 2

1 如果表a 还有其他字段，比如字段c，c可以做主键，保证a表记录重复，如果没有C，自行添加c字段做表a主键
2 select *
from a a1, a a2
where a1.b=a2.b and a1.c<>a2.c

Answer 3

select * from a where b in (select b from a group by b having count(*)>1)

Answer 4

select b
from A
group by b
having count (*)>1

Answer 5

select * from A where b in(select b from A group by b having count(b)>1);
刚亲自试过的。