mysql如何实现row_number详解

发布时间：2023-09-02 13:58:14 所属栏目：MySql教程来源：

导读：查询test表按group_id分组取sort_id前100个

SELECT id AS '原数据ID',group_id AS '分组ID',sort_id AS '排序条件',num AS '排名'

FROM

(SELECT @row_number := C

查询test表按group_id分组取sort_id前100个

SELECT id AS '原数据ID',group_id AS '分组ID',sort_id AS '排序条件',num AS '排名'

FROM

    (SELECT @row_number := CASE WHEN @customer_no = group_id THEN @row_number + 1 ELSE 1 END   AS num /*如果同group_id那么排名加1,否则更新为1*/

    ,@customer_no := group_id AS group_id /*重新加载group_id*/

    ,id , sort_id /*原有数据*/

FROM test,( SELECT @customer_no := 0,@row_number := 0) AS t

ORDER BY group_id ,sort_id DESC ,id)a

WHERE num<=100

（编辑：聊城站长网）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!