SQL 查询字段值相等或者重复数据

1.

select name , sex , age  from  tb group by name , sex , age  having count(*) > 1

2.

select * from tablename a
where (
  select count(*) from tablename
  where sex=a.sex and age=a.age 
  )>1

都可以，其中2列出所有条数据。