mysql单列去重复group by分组取每组前几条记录加order by排序

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        <a id="cb_post_title_url" class="postTitle2" href="/go.html?url=https://www.cnblogs.com/mengdejun/p/mysql_group_order_by.html">mysql单列去重复group by分组取每组前几条记录加order by排序</a>
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        <div id="cnblogs_post_body"><p>mysql分组取每组前几条记录(排名) 附group by与order by的研究，需要的朋友可以参考下</p><div class="post">