Lesson 1

When you look at Oracle, you will see more Internet-capable features than in any earlier release of Oracle's database. Oracle has answered the demand for integrating database data with other kinds of data used for the Internet, such as images and multimedia files.
In this module, we will examine some of the basic tools and technologies that have been added to Oracle specifically to enhance and simplify the development of Internet sites that combine database data and non-database files.

By the end of the module you will be able to:

1. Describe multimedia as it applies to a database
2. Describe how Java has been integrated into Oracle
3. List uses of the interMedia tool
4. Describe the Oracle Internet Directory and what it can do
5. Use SQLJ to deliver a Web page
6. List other tools and features that make Oracle good for Internet applications

The next lesson describes some multimedia concepts.

Many of the examples in this module focus on the use of SQL within the database. The examples assume that you can log in directly to an Oracle database or that you are using a client-based tool that allows you to enter commands into a database. With the introduction of web-based technologies, your ability to interact with the database has been augmented by new options. You still need to know SQL, but to take advantage of these options, you may need to understand Web listeners, new toolsets, languages such as Java, and application programming interfaces (APIs) such as JDBC and SQLJ.
Consider a simple architecture, shown in Figure 1 above, in which several computers are involved in the application consisting of several clients and a server. The database resides on the server, and the user interacts with the server via the client. The client and the server rely on the underlying network for their communications, and each runs a version of Oracle's Network Services tool. The server listens for Net Services requests issued by the client.

Now consider a three-tier architecture, shown in Figure 2 above. A three-tier architecture has three separate components: a client, an application server, and a database server. In implementing a three-tier architecture, you have many more choices available than you have in the traditional client-server architecture. The communications protocol used to communicate between the client and the application server can be different from that used to communicate between the application server and the database server. The workload distribution among the three components can vary widely across applications. The performance and reliability of the components in both stand-alone and networked mode can influence the success or failure of the application.