To become skilled in database application development as well as in database administration, you need to understand stored procedures and triggers. Since both stored procedures and triggers are coded in a database programming language, this chapter first provides background about the motivation and design issues for database programming languages as well as specific details about PL/SQL, the proprietary database programming language of Oracle.
After the background about database programming languages and PL/SQL, this chapter then presents stored procedures and triggers. For stored procedures, you will learn about the motivation and coding practices for simple and more advanced procedures. For triggers, you will learn about the classification of triggers, trigger execution procedures, and coding practices for triggers.
The presentation of PL/SQL details in Sections 11.1 to 11.3 assumes that you have had a previous course in computer programming using a business programming language such as Visual Basic, COBOL, or Java. If you would like a broader treatment of the material without the computer programming details, you should read Sections 11.1.1, 11.1.2, 11.3.1, and the introductory material in Section 11.2 before the beginning of Section 11.2.1. In addition, the trigger examples in Section 11.3.2 mostly involve SQL statements so that you can understand the triggers without detailed knowledge of PL/SQL statements.
For continuity, all examples about stored procedures and triggers use the revised university database of Chapter 10. Figure 11.1 in your textbook shows the Access relationship window of the revised university database for convenient reference.