摘要： select *, rank() over (order by 成绩 desc) as ranking, dense_rank() over (order by 成绩 desc) as dese_rank, row_number() over (order by 成绩 desc) as row_nu 阅读全文

摘要： ROW_NUMBER() OVER(PARTITION BY ... ORDER BY ...)RANK() OVER(PARTITION BY ... ORDER BY ...)DENSE_RANK() OVER(PARTITION BY ... ORDER BY ...)COUNT() OVER 阅读全文

摘要： 在平时的开发任务中我们经常会用到MYSQL的GROUP BY分组， 用来获取数据表中以分组字段为依据的统计数据。比如有一个学生选课表，表结构如下： Table: Subject_Selection Subject Semester Attendee ITB001 1 John ITB001 1 Bo 阅读全文