For programmers, dealing with data is just too complicated. First, there's the mismatch between object languages and relational databases. Then, there are all those sources of data to contend with: from XML documents to file systems to in-memory objects. Say you're working with .NET. Knowing VB or C# isn't enough: You need to deal with SQL, XML, XPath, ADO.NET, System.XML, and whatever else. LINQ eliminates this complexity. That's why .NET developers are so excited about it -- and it's why you'll be so excited about LINQ in Action.
This book teaches LINQ from soup to nuts: what it is, and how to use it to simplify and unify all forms of data access. The authors illuminate LINQ's consistent syntax, programming model, and "language-integrated query" concept, and teach techniques that'll work whether your data's stored in an RDBMS or an array.
The authors treat each LINQ "provider" in detail: LINQ to Objects, LINQ to SQL, LINQ to XML, LINQ to DataSet, and LINQ to Entities (which works with the ADO.NET Entity Framework). You'll find plenty of brief, concise code linked to specific tasks -- but you'll also find more sophisticated code designed to solve problems that would otherwise trip you up in the real world.
For example, LINQ now supports queries to generic collections. But what if your .NET code doesn't yet use generics? The authors walk you through a solution. For example, again: Often, you won't want to present data directly to the user -- you'll want to filter, sort, and format it first. LINQ handles that easily, but there are gotchas (What if the user doesn't provide values for all query criteria?). Again, this book offers solutions. You can tell these authors are really doing production work with LINQ -- and if you intend to, that's the kind of help you want.