1.
小虎的数学成绩是多少马老师教了那些课程数学最高分的同学是哪个同学
#小虎的数学成绩是多少#select s.sname,c.name,ss.scroe from students as s , coutses as c , scoros as ss where s.sid=ss.sid and c.cid=ss.sid and s.sname="小虎" and c.name="数学"#马老师教了那些课程#select c.name from teachers as t , coutses as c where t.tid=c.tid and t.name="马老师"#数学最高分的同学是哪个同学#SELECT s.sname,ss.scroe FROM students as s , coutses as c ,scoros as ss where s.sid=ss.sid and c.cid=ss.cid and c.name="数学" ORDER BY ss.scroe desc limit 1
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SELECT a.class,e.course,AVG(e.score) as '平均成绩' FROM account as a , exam as e where a.id=e.aid GROUP BY e.course
