常见数据库面试题（一）

（1）SELECT s.s_id,s.name,s.score,sc.c_id,c.c_name from student s LEFT JOIN student_class sc on s.s_id = sc.s_id LEFT JOIN class c on sc.c_id=c.c_id where (s.score>80 or s.score in(60,61,62)) and c.c_name='一班';
（2）SELECT sc.s_id,c.c_name,COUNT(s.sex),AVG(s.score) from student_class sc LEFT JOIN class c on sc.c_id=c.c_id LEFT JOIN student s on sc.s_id = s.s_id where s.sex='女' group BY c.c_name ORDER BY c.c_id asc;

select name from student where name not in (select  name from student where fenshu <=80);