由于笔试题遇到按类别进行累加的题,所以下面来总结以下:
有下面这组数据
表名:test
字段:ID,NAME,NUM
按类别逐行累加
select a.ID,a.`NAME`,SUM(b.NUM) from test as a ,test as b where a.`NAME` = b.`NAME`
and a.ID>=b.ID group by a.ID,a.`NAME`
结果如下:
按num从小到大排序后逐行累加
create view view1 as
select ID,`NAME`,NUM,row_number