答案:4_2(需另建一個臨時表:cc.dbf 屬性為: cname ,sum,cxi )
clear 例如: 高數(shù) 1 物理
set talk off
use cc
index on teacher to liu
total on teacher to yu fields 課程數(shù)
use yu
list off
?
use cc
sum 課程數(shù) to a
?“課程總數(shù):”
?? str(a)
答案:4_3
clear
set talk off
select sname,cname,grade;
from s,sc,c1;
where s.sno=sc.sno and c1.cno=sc.cno and c1.cno='1000';
order by sc.grade desc
set talk on
答案:4_4
clear
set talk off
select s.sno,s.sname,c1.cname,sc.grade;
from s,c1,sc;
where s.sno=sc.sno and c1.cno=sc.cno;
and s.age in(select age;
from s;
where sname='古天樂')
set talk on