请问一个sql语句怎么写

[yaya_sky]

是一个文章系统,有article表和class表


article表结构
================
id classid articlename 等


class表
=====================
classid classname classcount



我想执行一个sql 语句后重新统计下分类文章的下数目,

我这样写
update set classcount=(select count(id) from article group by classid) from article


这样好像不行啊
应该怎么写呢?如果用sql语句不行,存储过程应该怎么写呢?帮帮俺谢谢

[itblog]

update class
set classcount=b.num
from (
select classid,count(*) as num from article b group by classid) b
inner join class a on b.classid=a.classid