有 3 个表(15 分钟)
- Student 学生表 (学号,姓名,性别,年龄,组织部门)
- Course 课程表 (编号,课程名称)
- Sc 选课表 (学号,课程编号,成绩)
表结构如下: - 1)写一个 SQL 语句,查询选修了’计算机原理’的学生学号和姓名(3 分钟)
- 2)写一个 SQL 语句,查询’周星驰’同学选修了的课程名字(3 分钟)
- 3)写一个 SQL 语句,查询选修了 5 门课程的学生学号和姓名(9 分钟)
答:1)SQL 语句如下:select stu.sno, stu.sname from Student stu where (select count(*) from sc where sno=stu.sno and cno = (select cno from Course where cname='计算机原理')) != 0;
2)SQL 语句如下:
select cname from Course where cno in ( select cno from sc where sno = (select sno from Student where sname='周星驰'));
3)SQL 语句如下:
select stu.sno, stu.sname from student stu where (select count(*) from sc where sno=stu.sno) = 5;