In this chapter you learned about triggers. Here are some projects that will help you test the depth of your understanding:
1)
Create the following trigger : Create or modify a trigger on the ENROLLMENT table that fires before an INSERT statement. Make sure all columns that have NOT NULL and foreign key constraints defined on them are populated with their proper values.
2)
Create the following trigger : Create or modify a trigger on the SECTION table that fires before an UPDATE statement. Make sure that the trigger validates incoming values so that there are no constraint violation errors.
The projects in this section are meant to have you utilize all of the skills that you have acquired throughout this chapter. The answers to these projects can be found in Appendix D and at the companion Web site to this book, located at http://authors.phptr.com/rosenzweig3e. Visit the Web site periodically to share and discuss your answers.
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