When we wrote the first edition of this book, Oracle9i had just come out, and we managed to cover some of the interesting and new features in that release of the database. Now, Oracle Database 10g has just been released, and there are even more new features to talk about:
A new, MODEL clause has been added to the SELECT statement, enabling you to write queries that perform spreadsheet-like calculations against multidimensional arrays created from data you select from the database.
Oracle has added support for using regular expressions from SQL, and with a vengeance. Not only can you use regular expressions to select data, but also to manipulate data in various, useful ways. For example, you can perform regular expression search-and-replace operations. No other database vendor that we know of offers such powerful, regular expression functionality.
XML is everywhere these days, and that hasn't gone unnoticed in the world of SQL. The ANSI/ISO folk have created the SQL/XML standard, which defines mechanisms for selecting relational data and presenting it in XML form. Oracle supports this standard, which involves several, new SQL functions. Oracle also now supports XML as a native data type.
These are just the big features, which, of course, we cover in this second edition. In addition, we cover many small updates to Oracle SQL, such as the multiset union operators that enable you to perform set operations involving nested table collections.
Finally, we've worked carefully together as a team, not only with each other, but also with our editor, to ensure that all examples in this book are drawn from a single data set. You'll be able to download that data set from this book's catalog page. You can then use it to follow along with our examples.