更多“删除视图STUDENT的命令是( )。A.DELETE STUDENT VIEWB.DELETE STUDETNC.DROP STUDENT VIEWD.DROP ”相关问题
  • 第1题:

    为choose表添加外键约束,约束名为choose_student_fk,外键为student_no,连接到 student表的stuednt_no字段,以下命令正确的是______。

    A.alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) ;

    B.alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) REFERENCES student(stuednt_no);

    C.alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) REFERENCES student;

    D.alter table choose add constraint choose_student_fk REFERENCES student(stuednt_no);


    alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) REFERENCES student(stu_no);

  • 第2题:

    4、为choose表添加外键约束,约束名为choose_student_fk,外键为student_no,连接到 student表的stuednt_no字段,以下命令正确的是______。

    A.alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) ;

    B.alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) REFERENCES student(stuednt_no);

    C.alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) REFERENCES student;

    D.alter table choose add constraint choose_student_fk REFERENCES student(stuednt_no);


    D

  • 第3题:

    有3×4的结构矩阵student,每个结构有name(姓名)、scores(分数)两个成员,其中scores是以1×5矩阵表示的5门课的成绩,那么要删除第4个学生的第2门课成绩,应采用的正确命令是()。

    A.rmfield(student(1,2).scores(2))

    B.rmfield(student(4).scores)

    C.student(4).scores(2)=0

    D.student(1,2).scores(2)=[]


    student(1,2).scores(2)=[]

  • 第4题:

    选择数据库db_student为当前数据库的命令是()

    A.USE db_student;

    B.OPEN db_student;

    C.SELECT db_student;

    D.USE DATABASE db_student;


    set database to 教师.DBC

  • 第5题:

    为choose表添加外键约束,约束名为choose_student_fk,外键为student_no,参照 student表的st_no字段,以下SQL语句片段正确的是()。

    A.constraint choose_student_fk FOREIGN KEY (student_no);

    B.constraint choose_student_fk FOREIGN KEY (student_no) REFERENCES student(st_no);

    C.constraint choose_student_fk FOREIGN KEY (st_no) REFERENCES student(student_no);

    D.constraint choose_student_fk REFERENCES student(st_no);


    alter table choose add constraint choose_student_fk FOREIGN KEY (student_no) REFERENCES student(stu_no);