1. insert into buser values('test','學生','男',19);
2. update article set readcnt=readcnt+2 where title='開站囉！' ;

3. select days as 砍文章天數,count(*) as 討論區數目  from board group by days order by count(*) desc 
4. select * from buser order by age asc limit 1;
5. select max(readcnt) as 最高閱讀次數 from article ;

6. select buser.sex as 性別,sum(article.readcnt) as 總閱讀數 from buser,article 
   where buser.uid=article.uid
   group by buser.sex order by sum(article.readcnt) desc

7. select uid as 作者,sum(readcnt) as 總閱讀數 from article where score>9 group by uid order by sum(readcnt) asc

8. select buser.level as 身份,count(*) as 討論區個數 from board,buser
   where board.adm=buser.uid group by buser.level order by count(*) DESC
9. select board.stype as 分類,avg(article.readcnt) as 平均閱讀次數  from article,board,buser
	where article.bid=board.bid and buser.uid=article.uid
	and buser.level='教師' group by board.stype order by avg(article.readcnt) asc 

10. select uid,age from buser where uid like '%n%' ;