SQL语法：同一个表中某两个字段相同的现实出来！！！！

select 表名.* from 表名
inner join
(select 字段A,字段B from 表名 group by 字段A,字段B having count(*)>1)
as a
on 表名.字段A=a.字段A
and 表名.字段B=a.字段B

select 字段1,字段2,count(*) from table group by 字段1,字段2 having count(*)>1;

试试

字段A的值=字段B的值？还是A 或者B中出现重复的数据！

select A,B from table_name group by A,B;

方法一：
select t1.* from table_name t1,table_name t2 where t1.a=t2.a and t1.b=t2.b and t1.c<>t2.c;
方法二：
select t1.* from table_name t1
inner join
(select a,b from table_name group by a,b having count(*)>1)
t2
on t1.a=t2.a
and t1.b=t2.b