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Press Release: May 7, 2003

How to Get Consistent Data Access--Connected or Disconnected: O'Reilly Releases "ADO.NET in a Nutshell"

Sebastopol, CA--Almost every software application today is driven by data, and whether they're working with the Web, Windows, a distributed network, a web service, or something entirely different, developers are faced with a whole stable of dissimilar databases to connect to. Microsoft helped simplify this quandary with ActiveX Data Objects (ADO), an object-oriented interface that enabled Windows applications to access a variety of databases, including Oracle, SQL Server, and DB2. Now, with the advent of the .NET platform, Microsoft has gone a step further. While ADO.NET bears some resemblance to its ADO predecessor, this new framework offers some dramatic changes--particularly its "disconnected" programming model.

"ADO.NET is substantially different than Microsoft's previous data access technologies," explains Matthew MacDonald, coauthor with Bill Hamilton of ADO.NET in a Nutshell (O'Reilly, US $69.95). "In previous versions of ADO, 'disconnected' access was an afterthought. In ADO.NET, it's a core abstraction. Developers need to understand the basics of this new disconnected paradigm before they start programming with it."

Understanding the basics--and more--is exactly what "ADO.NET in a Nutshell" is designed to help developers do. The book offers an objective introduction to ADO.NET, plus a comprehensive section that explains how to use ADO.NET's core classes, and a quick reference on the ADO.NET namespaces and object model. Current with the .NET Framework 1.1, the book also includes a CD that enables developers to integrate the quick reference section into the help files of Visual Studio .NET.

As the book points out, .NET developers need to master ADO.NET if they are to build applications or web services that rely on database access, especially enterprise applications. Primarily, they need to understand ADO.NET's two programming environments: connected and disconnected. The connected environment provides forward only, read-only access to data in the data source and the ability to execute commands against the data source. The connected classes provide a common way to work with connected data regardless of the underlying data source. The disconnected environment allows data to be retrieved and manipulated offline in a DataSet, which is an in-memory database completely independent of the original data source. "ADO.NET in a Nutshell" helps developers decide which access strategy to use. "They'll know when they should use quick-and-dirty connection-based access," MacDonald explains, "and when they need to retain disconnected data in a DataSet, and use ADO.NET's more advanced features."

"ADO.NET in a Nutshell" provides numerous practical examples using the C# programming language, and covers a variety of issues that programmers face, such as ways to use ADO.NET to convert data into XML, and the possibilities and limitations of cross-platform programming--using the DataSet and XML to interact with a Java client, for example. MacDonald notes that this single-source reference is not only for programmers familiar with the .NET platform who need to get a jumpstart on ADO.NET, but for seasoned .NET developers who want to sharpen their skills even further. "Learning to use ADO.NET takes a little work," he says, "but the rewards are well worth it."

Additional Resources:

ADO.NET in a Nutshell
Bill Hamilton and Matthew MacDonald
ISBN 0-596-00361-7, 599 pages, $44.95 (US), $69.95 (CAN), 31.95 (UK)
1-800-998-9938; 1-707-827-7000

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