Microsoft Cloud Authors: Elizabeth White, Yeshim Deniz, Serafima Al, Janakiram MSV, John Katrick

Related Topics: Microsoft Cloud

Microsoft Cloud: Article

Book Review: Pro LINQ

Language Integrated Query in C# 2008

As promised by the author, this book starts with code (“Hello LINQ”), ends with code (a query joining database data with XML data), and is code-heavy in the middle. All the code runs and the output is listed in the book. The code snippets you can steal will quickly recoup the price of the book.

It’s divided into five parts: Introduction, LINQ to Objects, LINQ to XML, LINQ to DataSet, and LINQ to SQL.

Part One has two chapters. In the first chapter, “Hello LINQ,” the author shows how to use LINQ to query XML and SQL databases, and adds that LINQ can also work with DataSets, object, and Entities. He also points out that LINQ (Language Integrated Query) is more of a data-iteration engine, but that Microsoft didn’t want to name its hot new technology “DIE”! Yep, Joseph has a sense of humor, and it pops up from time to time in this book.

The second chapter covers the language enhancements in C# and VB.NET to support LINQ. Note I didn’t specify the version of C# or VB.NET. That’s because the building blocks of LINQ have been being added in one by one since .NET version 2.0. In some cases the author goes into some detail on what problem the language addition was meant to address, and how the addition addresses the problem. The chapter ends with eight pages of details on how the compiler translates LINQ into C# or .NET code. Joseph admits that you’re about as likely to need this information as you need to know what machine code is generated for a foreach loop, but I find it interesting, and I’m impressed that he dug the information up.

The second part covers LINQ to objects, serving also as an overall introduction to LINQ. After a quick intro to LINQ in Chapter Three, Chapter Four covers deferred operations, so-called because they return a type of IEnumerable<T> that will be iterated through at a later time. Chapter Five covers non-deferred types, so-called because they immediately return values of types other than IEnumerable<T>. An example of this would be conversion routines such as ToList.

Part three covers LINQ to XML, with Chapter Six kicking things off with a description of creating a simple XML document using DOM to show the amount of code involved so we can see how big an improvement LINQ to XML is. Chapter Seven covers the LINQ XML API, and discusses the “Halloween” problem, so-called because it was first discussed by experts on Halloween. The problem occurs if part of an XML document is modified while a LINQ query is still iterating over it. Chapter Eight covers LINQ-to-XML operators, such as “DescendantNodes,” which return a sequence containing the descendant nodes of each element or document. Chapter Nine covers transformations and validation. If you plan on using LINQ and XML, the code snippets in this section are worth their weight in gold.

Part four consist of two very short chapters covering LINQ to DataSet. The author chose to cover LINQ DataSet operations before covering LINQ to SQL because LINQ to SQL only works with Microsoft SQL Server, where you can retrieve DataSets from almost any database and then use LINQ to query the results. Chapter 10 covers DataRow and DataTable operators. Chapter 11 quickly covers typed DataSets. As I said, it’s a short section.

The fifth and final part covers LINQ to SQL. Chapter 12 is another short chapter that introduces us to LINQ to SQL. The author points out that most technologies that link relational databases to business classes lose the ability to do queries against the classes. He then discusses a bit about how entity-mapping classes solve this problem by allowing LINQ to run queries and even updates against classes created from SQL databases.

In Chapter 13 the author gives tips and discusses tools. Joseph points out that if we don’t understand his tips now, he’s done his job, because he wants to give us tips before we need them, not after we’ve learned we need them the hard way. The tools he discusses are SQLMetal and Object Relational Designer. Both are included in the .NET 3.5 Framework.

Chapter 14, “LINQ to SQL Database Operations,” is described as “a whirlwind tour of standard database operations.” It covers such things as how LINQ-to-SQL queries are executed in the database, and the issues caused by the fact that LINQ stands for “Language Integrated Query,” where queries are written as close to the programming language (C# in our case) as possible, but have to be translated into true SQL for execution. This, for example,

where c.CustomerID.TrimEnd(‘k’) == “Lazy”

throws an error because TrimEnd is not valid SQL.

where c.CustomerID == “Lazy”. TrimEnd(‘k’)

executes without error because TrimEnd is a valid .NET function. Understand the difference? If not, buy the book and let Joseph explain it. Simply put, in this case the left side is evaluated by SQL and the right side is evaluated by C#.

Chapter 15 covers LINQ-to-SQL entity classes, including generating entity classes, extending entity classes with partial methods, and important System.Data.Linq API classes. Chapter 16 is a long chapter covering the details of the DataContext class, including example code for many of its functions. Chapter 17 covers detecting and resolving concurrency conflicts including pessimistic concurrency and transactions. The final chapter, Chapter 18, covers views, entity class inheritance, and more information on transactions.

This is a well-written book, full of tips and traps, with enough source code snippets to make it worth buying for that reason alone. It’s value-packed with information from someone who clearly knows what he’s talking about. It’s one of the better books I’ve seen on LINQ and will be a welcome addition to my bookshelf.

Title: Pro LINQ: Language Integrated Query in C# 2008
Author: Joseph C. Rattz, Jr.
Publisher: Apress
ISBN: 978-1-59059-789-7
Price: U.S. $44.99

More Stories By Dennis Hayes

Dennis Hayes is a programmer at Georgia Tech in Atlanta Georgia where he writes software for the Adult Cognition Lab in the Psychology Department. He has been involved with the Mono project for over six years, and has been writing the Monkey Business column for over five years.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.

@ThingsExpo Stories
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
Imagine if you will, a retail floor so densely packed with sensors that they can pick up the movements of insects scurrying across a store aisle. Or a component of a piece of factory equipment so well-instrumented that its digital twin provides resolution down to the micrometer.
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settle...
Product connectivity goes hand and hand these days with increased use of personal data. New IoT devices are becoming more personalized than ever before. In his session at 22nd Cloud Expo | DXWorld Expo, Nicolas Fierro, CEO of MIMIR Blockchain Solutions, will discuss how in order to protect your data and privacy, IoT applications need to embrace Blockchain technology for a new level of product security never before seen - or needed.
BnkToTheFuture.com is the largest online investment platform for investing in FinTech, Bitcoin and Blockchain companies. We believe the future of finance looks very different from the past and we aim to invest and provide trading opportunities for qualifying investors that want to build a portfolio in the sector in compliance with international financial regulations.
Leading companies, from the Global Fortune 500 to the smallest companies, are adopting hybrid cloud as the path to business advantage. Hybrid cloud depends on cloud services and on-premises infrastructure working in unison. Successful implementations require new levels of data mobility, enabled by an automated and seamless flow across on-premises and cloud resources. In his general session at 21st Cloud Expo, Greg Tevis, an IBM Storage Software Technical Strategist and Customer Solution Architec...
Nordstrom is transforming the way that they do business and the cloud is the key to enabling speed and hyper personalized customer experiences. In his session at 21st Cloud Expo, Ken Schow, VP of Engineering at Nordstrom, discussed some of the key learnings and common pitfalls of large enterprises moving to the cloud. This includes strategies around choosing a cloud provider(s), architecture, and lessons learned. In addition, he covered some of the best practices for structured team migration an...
No hype cycles or predictions of a gazillion things here. IoT is here. You get it. You know your business and have great ideas for a business transformation strategy. What comes next? Time to make it happen. In his session at @ThingsExpo, Jay Mason, an Associate Partner of Analytics, IoT & Cybersecurity at M&S Consulting, presented a step-by-step plan to develop your technology implementation strategy. He also discussed the evaluation of communication standards and IoT messaging protocols, data...
Coca-Cola’s Google powered digital signage system lays the groundwork for a more valuable connection between Coke and its customers. Digital signs pair software with high-resolution displays so that a message can be changed instantly based on what the operator wants to communicate or sell. In their Day 3 Keynote at 21st Cloud Expo, Greg Chambers, Global Group Director, Digital Innovation, Coca-Cola, and Vidya Nagarajan, a Senior Product Manager at Google, discussed how from store operations and ...
In his session at 21st Cloud Expo, Raju Shreewastava, founder of Big Data Trunk, provided a fun and simple way to introduce Machine Leaning to anyone and everyone. He solved a machine learning problem and demonstrated an easy way to be able to do machine learning without even coding. Raju Shreewastava is the founder of Big Data Trunk (www.BigDataTrunk.com), a Big Data Training and consulting firm with offices in the United States. He previously led the data warehouse/business intelligence and B...
"IBM is really all in on blockchain. We take a look at sort of the history of blockchain ledger technologies. It started out with bitcoin, Ethereum, and IBM evaluated these particular blockchain technologies and found they were anonymous and permissionless and that many companies were looking for permissioned blockchain," stated René Bostic, Technical VP of the IBM Cloud Unit in North America, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Conventi...
When shopping for a new data processing platform for IoT solutions, many development teams want to be able to test-drive options before making a choice. Yet when evaluating an IoT solution, it’s simply not feasible to do so at scale with physical devices. Building a sensor simulator is the next best choice; however, generating a realistic simulation at very high TPS with ease of configurability is a formidable challenge. When dealing with multiple application or transport protocols, you would be...
Smart cities have the potential to change our lives at so many levels for citizens: less pollution, reduced parking obstacles, better health, education and more energy savings. Real-time data streaming and the Internet of Things (IoT) possess the power to turn this vision into a reality. However, most organizations today are building their data infrastructure to focus solely on addressing immediate business needs vs. a platform capable of quickly adapting emerging technologies to address future ...
We are given a desktop platform with Java 8 or Java 9 installed and seek to find a way to deploy high-performance Java applications that use Java 3D and/or Jogl without having to run an installer. We are subject to the constraint that the applications be signed and deployed so that they can be run in a trusted environment (i.e., outside of the sandbox). Further, we seek to do this in a way that does not depend on bundling a JRE with our applications, as this makes downloads and installations rat...
Widespread fragmentation is stalling the growth of the IIoT and making it difficult for partners to work together. The number of software platforms, apps, hardware and connectivity standards is creating paralysis among businesses that are afraid of being locked into a solution. EdgeX Foundry is unifying the community around a common IoT edge framework and an ecosystem of interoperable components.
DX World EXPO, LLC, a Lighthouse Point, Florida-based startup trade show producer and the creator of "DXWorldEXPO® - Digital Transformation Conference & Expo" has announced its executive management team. The team is headed by Levent Selamoglu, who has been named CEO. "Now is the time for a truly global DX event, to bring together the leading minds from the technology world in a conversation about Digital Transformation," he said in making the announcement.
In this strange new world where more and more power is drawn from business technology, companies are effectively straddling two paths on the road to innovation and transformation into digital enterprises. The first path is the heritage trail – with “legacy” technology forming the background. Here, extant technologies are transformed by core IT teams to provide more API-driven approaches. Legacy systems can restrict companies that are transitioning into digital enterprises. To truly become a lead...
Digital Transformation (DX) is not a "one-size-fits all" strategy. Each organization needs to develop its own unique, long-term DX plan. It must do so by realizing that we now live in a data-driven age, and that technologies such as Cloud Computing, Big Data, the IoT, Cognitive Computing, and Blockchain are only tools. In her general session at 21st Cloud Expo, Rebecca Wanta explained how the strategy must focus on DX and include a commitment from top management to create great IT jobs, monitor ...
"Cloud Academy is an enterprise training platform for the cloud, specifically public clouds. We offer guided learning experiences on AWS, Azure, Google Cloud and all the surrounding methodologies and technologies that you need to know and your teams need to know in order to leverage the full benefits of the cloud," explained Alex Brower, VP of Marketing at Cloud Academy, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clar...
The IoT Will Grow: In what might be the most obvious prediction of the decade, the IoT will continue to expand next year, with more and more devices coming online every single day. What isn’t so obvious about this prediction: where that growth will occur. The retail, healthcare, and industrial/supply chain industries will likely see the greatest growth. Forrester Research has predicted the IoT will become “the backbone” of customer value as it continues to grow. It is no surprise that retail is ...