• 2022-06-08
    请把下面代码补充完整。( )
    A: 息工程系全体学生的成绩置零。
    B: DATE SC
    C: > Grade=0
    D: ERE Sno IN (SELETE Sno
    E: OM Student
    F: ERE Sdept= 'IS' );
    G: UPDATE
  • B

    举一反三

    内容

    • 0

      若查询考试成绩不为空的学生的学号,下列语句哪个是正确的?( ) A: SELECT Sno FROM SC WHERE Grade >= 0; B: SELECT Sno FROM SC WHERE Grade != 0; C: SELECT Sno FROM SC WHERE Grade IS NOT NULL; D: SELECT Sno FROM SC WHERE Grade NOT IS NULL;

    • 1

      针对学生选课表sc(sno, cno, grade),其中sno为学号,cno为课程号,grade为成绩。以下( )语句可查询选修了两门以上成绩在90分以上课程的学生学号。 A: select sno from sc where grade>90 group by sno having count(cno)>2; B: select sno from sc where grade>90 group by sno having count(*)>2; C: select sno from sc where grade>90 and count(*)>2 group by sno; D: select sno from sc where grade>90 group by sno having count(sno)>2;

    • 2

      在学生选课数据库中有学生表student(sno,sname,ssex,sage,sdept),课程表course(cno,cname)及学生选课表sc(sno,cno,grade),其中sno是学号,sname是姓名,ssex是性别,sage是年龄,sdept是系别,cno是课程号,cname是课程名,grade是成绩。以下哪条语句可以实现查询选了课的学生人数( )。 A: select count(*) from sc B: select count(sno) from sc C: select count(distinct sno) from sc D: select count(cno) from sc

    • 3

      使用教学(STC)数据库,请将实现以下功能的SQL语句填写完整:: (10)将计算机系('CS')学生的成绩提高10%。[br][/br] update sc set grade= grade * where sno in[br][/br] (select sno from student where )

    • 4

      查询每个学生的学号、姓名、选修的课程名及成绩,下列()的操作是正确的。 A: select student,sno,sname,grade from student,sc where student.sno=sc.sno and sc.cno=course.cno B: select student,sno,sname,grade from student,sc,cource where student.sno=sc.sno C: select student,sno,sname,grade from student,sc,cource where sc.cno=course.cno D: select student,sno,sname,grade from student,sc,cource where student.sno=sc.sno and sc.cno=course.cno