icp网站备案,南昌网站seo公司,匿名ip访问网站受限,搭建h5流程mysql中实现排名的方法#xff1a;使用demo函数#xff0c;语法为【SELECT banji,avg(score) as AvgS FROM table_test GROUP BY banji ORDER BY AvgS DESC】。mysql中实现排名的方法#xff1a;可用Demo实现注意里面的A#xff0c;属于嵌套查询#xff0c;所以排名会正确…mysql中实现排名的方法使用demo函数语法为【SELECT banji,avg(score) as AvgS FROM table_test GROUP BY banji ORDER BY AvgS DESC】。mysql中实现排名的方法可用Demo实现注意里面的A属于嵌套查询所以排名会正确。FROM(SELECT A.*,rank:rank1 as pmFROM(SELECT banji,avg(score) as AvgS FROM table_test GROUP BY banji ORDER BY AvgS DESC) A ,(SELECT rank:0) B) MORDER BY M.banji如果里面没有子查询使用下面的SQL那么排序会出错。出错的取决于GROUP BY 是否有多于一条的分组。SELECT banji,avg(score) as AvgS ,rank:rank1 as pmFROM table_test A,(SELECT rank:0) BGROUP BY banjiORDER BY AvgS DESC原因rank排名发生在GROUP BY 之前。GROUP BY 是对排名后的结果进行分组。如果想对分组后的结果进行排名请使用子查询。更多相关免费学习推荐mysql教程(视频)
