说明：  本书介绍了SOL和Oracle数据库的最基本的知识，以及如何操作这两种数据库，通过这本书的学习，我们能学习到如何对数据库操作。
(This book describes the SOL and the most basic knowledge of Oracle databases, as well as how to operate these two kinds of databases, through the study of this book, we can learn how to operate the database.)