mysql 相同某一列的值相同

查找 相同firstorder的值相同的数据 (我只取出id,firstorder)

SELECT id , firstorder
FROM dede_archives AS a
WHERE a.firstorder
IN (
SELECT firstorder
FROM dede_archives b
WHERE b.id != a.id
) order by firstorder

SELECT id,typeid,firstorder
FROM dede_archives AS a
WHERE a.firstorder
IN (
SELECT firstorder
FROM dede_archives b
WHERE b.id != a.id and a.typeid=b.typeid
) order by firstorder;