查询选修了'数据库基础'课程的同学的学号,和这些同学选修的全部课程号和分数.select sno,cno,gradefrom ______________________
A: sc where sno in (select sno from sc join course on sc.cno=course.cno where cname='数据库基础')
B: sc join course on sc.cno=course.cno where cname='数据库基础'
C: sc where sno in (select sno from course where cname='数据库基础')
D: sc where cno in (select cno from course where cname='数据库基础')
A: sc where sno in (select sno from sc join course on sc.cno=course.cno where cname='数据库基础')
B: sc join course on sc.cno=course.cno where cname='数据库基础'
C: sc where sno in (select sno from course where cname='数据库基础')
D: sc where cno in (select cno from course where cname='数据库基础')
举一反三
- 同时选修了‘数据结构’和‘操作系统’2门课程的同学学号、姓名。select student.sno,sname from student,sc,coursewhere student.sno=sc.sno and course.cno=sc.cnoand _________________________________________________ A: cname='数据结构' and student.sno in(select sno from sc,course where sc.cno=course.cno and cname='操作系统') B: cname='操作系统' and student.sno in(select sno from sc,course where sc.cno=course.cno and cname='数据结构') C: cname='数据结构' and cname='操作系统' D: student.sno in(select sno from sc,course where sc.cno=course.cno and cname='操作系统'and cname='数据结构')
- 基于学生—选课—课程数据库中的三个基本表：学生的信息表：STUDENT(sno, sname, sex, age, dept)主码为sno课程信息表：COURSE(cno,cname, teacher)主码为cno学生选课信息表：SC(sno, cno, grade)主码为(sno, cno) “查询没有学习成绩的学生的学号和课程号”的SQL语句是（）。 A: SELECT sno, cno FROM SC WHERE grade=NULL B: SELECT sno, cno FROM SC WHERE grade IS" C: SELECT sno, cno FROM SC WHERE grade IS NULL D: SELECT sno, cno FROM SC WHERE grade="
- 查询没有选数据库基础课程的同学学号和姓名。select sno,sname from student where ____________(select ______ from sc ,course where _______________ and cname='数据库基础') A: not exists；* ; course.cno=sc.cno and student.sno=sno B: not exists；sno ; course.cno=sc.cno and student.sno=sc.sno C: sno not in ; sno ; course.cno=sc.cno D: sno not in ; * ; course.cno=sc.cno and student.sno=sc.sno
- 下列查询中,属于相关子查询的有（）。 A: SELECT * FROM student WHERE sno IN (SELECT sno FROM sc WHERE cno='1'); B: SELECT sno, cno FROM SC x WEHRE grade>=(SELECT AVG(grade) FROM SC y WHERE y.sno = x.sno); C: SELECT sname FROM student WHERE EXISTS(SELECT * FROM sc WHERE sno=student.sno AND cno='1'); D: SELECT sname FROM student WHERE NOT EXISTS(SELECT * FROM course WHERE NOT EXISTS(SELECT * FROM sc WHERE sc.sno=student.sno AND sc.cno=course.cno));
- 有关系S(SNO, SNAME, SAGE)，C(CNO, CNAME)，SC(SNO, CNO, GRADE)。其中SNO是学生号，SNAME是学生姓名，SAGE是学生年龄， CNO是课程号，CNAME是课程名称，GRADE是成绩。以下（ ）SQL语句可以实现查询选修了'C002'号课程的学生姓名。 A: SELECT SNAME FROM S, SC WHERE S.SNO=SC.SNO AND CNO='C002' B: SELECT SNAME FROM S WHERE SNO IN (SELECT SNO FROM SC WHERE CNO='C002') C: SELECT SNAME FROM S WHERE SNO = (SELECT SNO FROM SC WHERE CNO='C002') D: SELECT SNAME FROM S WHERE SNO NOT IN (SELECT SNO FROM SC WHERE CNO='C002')