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);
正确答案:C
答案解析:有
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