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You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty. Which statement accomplishes this task?()

  • A、ALTER TABLE students ADD PRIMARY KEY _ id;
  • B、ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);
  • C、ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;
  • D、ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
  • E、ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);

参考答案

更多 “You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty. Which statement accomplishes this task?()A、ALTER TABLE students ADD PRIMARY KEY _ id;B、ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);C、ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;D、ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);E、ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);” 相关考题
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考题 单选题You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty.Which statement accomplishes this task?()A ALTER TABLE students ADD PRIMARY KEY student_id;B ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student _ id);C ALTER TABLE students ADD CONSTRAINT stud _ id _pk PRIMARY KEY (student _ id);D ALTER TABLE students MODIFY CONSTRAINT stud _ id _pk PRIMARY KEY (student _ id);

考题 单选题You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty. Which statement accomplishes this task?()A ALTER TABLE students ADD PRIMARY KEY student_id;B ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);C ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;D ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);E ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);

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