Oracle PL/SQL in 10 Minutes, Sams Teach Yourself

Lesson 3. Working with Oracle

In this lesson, you learn how to connect and log in to Oracle, how to issue PL/SQL SQL statements, and how to create and populate the example tables that we’ll be using throughout this book.

Creating a Working Environment

Now that you have access to Oracle and client software to use with it, the next step is to create a working environment. Database servers, like your Oracle server, are usually used by lots of different users and applications. Imagine what would happen if a user created a table called customers to store customer data, and another user tried to create a table of the same name. Users could overwrite each other’s data; they could access incorrect information—you get the idea. In multi-user environments, ...