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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

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Foreign Key Constraint Example The following statement creates the dept_20 table and defines and enables a foreign key on