ocp题库怎么背:11g-051-V9.02-第177题
ocp题库怎么背:11g-051-V9.02-第177题,完整题库请点击这里联系老师咨询了解
177.You need to design a student registration database that contains several tables storing academic information.
The STUDENTS table stores information about a student. The STUDENT_GRADES table stores information about the student's grades. Both of the tables have a column named STUDENT_ID.The STUDENT_ID column in the STUDENTS table is a primary key.
You need to create a foreign key on the STUDENT_ID column of the STUDENT_GRADES table that points to the STUDENT_ID column of the STUDENTS table. Which statement creates the foreign key?
A. CREATE TABLE student_grades (student_id NUMBER(12),semester_end DATE, gpa
NUMBER(4,3), CONSTRAINT student_id_fk REFERENCES (student_id) FOREIGN KEY
students(student_id));
B. CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa
NUMBER(4,3), student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id));
C. CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa
NUMBER(4,3), CONSTRAINT FOREIGN KEY (student_id) REFERENCES students(student_id));
D. CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa
NUMBER(4,3), CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES
students(student_id));
Answer: D
试题解析:
Foreign Key Constraint Example The following statement creates the dept_20 table and defines and enables a foreign key on
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