Application Design and Development

Practically all use of databases occurs from within application programs. Correspondingly, almost all user interaction with databases is indirect, via application programs. Not surprisingly, therefore, database systems have long supported tools such as form and GUI builders, which help in rapid development of applications that interface with users. In recent years, the Web has become the most widely used user interface to databases.

In this chapter, we study tools and technologies that are used to build applications, focussing on interactive applications that use databases to store data.

After an introduction to application programs and user interfaces in Section 9.1,we focus on developing applicationswithWeb-based interfaces.We start with an overview ofWeb technologies in Section 9.2, and discuss the Java Servlets technology, which is widely used for buildingWeb applications, in Section 9.3. A short overview of Web application architectures in presented Section 9.4. In Section 9.5, we discuss tools for rapid application development, while in Section 9.6 we cover performance issues in building largeWeb applications. In Section 9.7, we discuss issues in application security. We conclude the chapter with Section 9.8, which covers encryption and its use in applications.