职位表(ID, Name) 求职表(UserID, s1, s2, s3)先创建个视图,存放求职数 Create View 求职数视图 As Select ID,Name,Count(Distinct UserID) as 求职数 From 职位表,求职表 Where 职位表.Name=求职数.s1 --这三个也可能是职位表.ID=求职数.sn,看你的数据库 or 职位表.Name=求职数.s2 or 职位表.Name=求职数.s3然后用视图排序 Select Name From 求职数视图 order by 求职数 Desc
Select s From ( Select s1 As s From TableName Union All Select s2 From TableName Union All Select s3 From TableName ) A Group By s Order By Count(s) Desc 这是代码,看看吧
你看看SQL的联机丛书看可以不..........
求职表(UserID, s1, s2, s3)先创建个视图,存放求职数
Create View 求职数视图 As
Select ID,Name,Count(Distinct UserID) as 求职数
From 职位表,求职表
Where 职位表.Name=求职数.s1 --这三个也可能是职位表.ID=求职数.sn,看你的数据库
or 职位表.Name=求职数.s2
or 职位表.Name=求职数.s3然后用视图排序
Select Name From 求职数视图 order by 求职数 Desc
(
Select s1 As s From TableName
Union All
Select s2 From TableName
Union All
Select s3 From TableName
) A
Group By s
Order By Count(s) Desc
这是代码,看看吧