sql_查询一张表中的重复数据

create table A(id int);

insert into A(id) values(1);insert into A(id) values(1);insert into A(id) values(2);insert into A(id) values(3);insert into A(id) values(3);insert into A(id) values(3);insert into A(id) values(4);insert into A(id) values(4);

select id ,count(1) from A group by id having count(1)>1;

通过以上SQL语句就可以查出表中重数出现的数据以及个数