Oracle® PL/SQL® Interactive Workbook, Second Edition

Chapter 13 Test Your Thinking

In this chapter, you have learned about functions. Here are some projects that will help you test the depth of your understanding.

1)	Write a stored function called new_student_id that takes in no parameters and returns a student.student_id%TYPE. The value returned will be used when inserting a new student into the CTA application. It will be derived by using the formula: student_id_seq.NEXTVAL.
2)	Write a stored function called zip_does_not_exist that takes in a zipcode.zip%TYPE and returns a Boolean.The function will return TRUE if the zipcode passed into it does not exist. It will return a FALSE if the zipcode exists. Hint: An example of how it might be used is as follows: DECLARE cons_zip CONSTANT zipcode.zip%TYPE ...