使用jxgl数据库，查询选修了课程的学生选修的门数，显示学号、姓名、选课门数select sno,sname,COUNT(sno)______ from Students join SC on Students.sno=SC.snogroup by sno______
举一反三
- 使用jxgl数据库，查询所有同学的选修课的门数，包括选修了课程和还未选修课程的同学。select sno,COUNT(*)______ from Students left join SC on Students.sno=SC.snogroup by sno______
- 在学生选课数据库中，查询选修了课程的学生的学号、姓名，SQL语句可为（ ） A: SELECT DISTINCT Sno, Sname FROM Student, SC WHERE Student.Sno = SC.Sno; B: SELECT Sno, Sname FROM Student, SC WHERE Student.Sno = SC.Sno; C: SELECT DISTINCT Sno, DISTINCT Sname FROM Student WHERE Student.Sno IN (SELECT Sno FROM SC); D: SELECT Sno, Sname FROM Student WHERE Student.Sno IN (SELECT DISTINCT Sno FROM SC);
- 查询选课门数大于3门的同学学号，姓名, 选课门数Select ______________from student s, scwhere s.sno=sc.sno group by __________having _____________ A: sno, sname, count(*) ; sno, sname; count(*)>3 B: sno, sname, count(*) ; sno; count(*)>3 C: sno, sname, count(cno) ; sno; count(cno)>3 D: sno, sname, count(sno) ; sno; count(sno)>3
- 以下SQL语句中，____________可以在“学生-课程”数据库正确实现“查询选修了课程的学生总人数”。 A: SELECT COUNT(Sno)FROM SC B: SELECT COUNT(DISTINCT Sno)FROM SC C: SELECT COUNT(*)FROM SC D: SELECT SUM(Sno)FROM SC
- 若要求“查询选修了3门以上课程的学生的学号”,正确的SQL语句是( ) A: SELECT sNo FROM SC GROUP BY sNo WHERE COUNT(*)> 3 B: SELECT sNo FROM SC GROUP BY sNo HAVING COUNT(*)> 3 C: SELECT sNo FROM SC ORDER BY sNo WHERE COUNT(*)> 3 D: SELECT sNo FROM SC ORDER BY sNo HAVING COUNT(*)> 3