Mysql查詢問(wèn)題，根據(jù)最新發(fā)布文章或最新評(píng)論查詢出前幾名用戶信息。

//文章的  評(píng)論的改一下表就好了
select tb_user.* from tb_article join tb_user on tb_user.id=tb_article.id order by tb_article.create_time desc limit 5;
//一起?效率...就沒(méi)怎么考慮233.....
SELECT
    a.uid,
    username
FROM
    (
        (
            SELECT
                `uid`,
                `create_time` AS `time`
            FROM
                tb_article
        )
        UNION ALL
            (
                SELECT
                    `uid`,
                    `create_time` AS time
                FROM
                    tb_comment
            )
    ) AS a
JOIN tb_userAS b ON a.uid = b.uid
GROUP BY
    a.uid
ORDER BY
    a.time DESC
LIMIT 5