With Apache Hadoop MapReduce, users who previously had to use a relational database to store data and process it using SQL queries can now play with mammoth sizes of unstructured data. MapReduce has simplified data analytics, and processing has become much simpler and, more importantly, scalable with MapReduce. Hadoop is by far the most widely used implementation of the MapReduce paradigm.

You can get started using the MapReduce framework on your own machine with a local mode installation of Hadoop. Simply unzip, configure, and you’re ready to write your first MapReduce example. Local mode is strictly for beginners who are getting started with Hadoop. You can find more on getting started with Hadoop on your machine on the official page.

Since MapReduce is ideal to process huge amounts of unstructured data, it naturally implies that you will require a sizeable compute and storage infrastructure for any serious Hadoop deployment. This is where Amazon EMR comes in. EMR which is short for Elastic MapReduce is a ready-made web service that offers MapReduce running on Amazon EC2. If you’re good at Amazon Web Services (AWS), it will only take you a couple of minutes to get an EMR service up and running. This article will walk you through this process. The best thing about EMR is that you do not have to take care of EC2 instance provisioning, since EMR takes care of firing up and shutting down new instances on demand. With Amazon EMR, you don’t have to worry about configuring a Hadoop cluster, so you can focus on crunching your big data.
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This is the second part in the Parallel Programming in Clojure series that introduces some advanced topics and functionalities for concurrency in Clojure. In Part 1, we gave an overview of concurrency in Clojure and covered some basic topics including Agents, Concurrency Macros, Futures and Java Interoperatability. In this Part 2 blog post, we will discuss some mutable types such as Refs and Atom along with their use cases and examples. We will also shed some light on fork/join parallelism through Reducers that should further enhance your understanding about the possibilities for using Clojure.
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Although Apache Hadoop was created to process huge amounts of unstructured data, especially on the Internet, you will find Hadoop sitting alongside a relational database. This stems from the prevalence of relational databases. You must also consider the fact that companies, individuals and teams considering a migration to Hadoop need to port their data to Hadoop so that MapReduce jobs can use it. Although you can configure and manually execute data migration, there are tools available to do this for you. One such tool is Sqoop (http://sqoop.apache.org), which was released by Cloudera, but now it’s an Apache project. As the name signifies, it scoops data from a relational source to HDFS, and vice versa.
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Node.js is a JavaScript platform for building networked applications. Node.js was not the first server-side JavaScript implementation, but it’s different from all the previous ones because it does I/O in a different way. The I/O operations are event-driven: instead of making sequential I/O operations, the developer defines functions that are called once a relevant event happens. Such an event can be, for instance, that a socket has a new connection or that data is available to be read from a socket. In this article we will take a look at using streams in Node.js, using the latest Streams2 API.
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The .NET Entity Framework (EF) is an object-relational database mapper that enables easy database access for .NET developers using domain-specific .NET objects that EF can generate for you. As we saw in my last blog post on Entity Framework, you can use EF to automatically create your application’s database from the classes you have in your code. It can even be used to migrate your database to newer versions as you add columns to your database or even add default rows when it first creates the database. While we won’t go into those features here, it helps to know that all that database goodness is available to you.

In my last blog post we used EF to create a SeminarContext database, and then, using the console application that we created, we added and displayed the rows in the database. We will be using that same database as the basis for this blog post so if you haven’t done so yet, you may want to read the previous post and work through that code.
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Safari Books Online continues to make learning easier for non-native speakers of English, with the addition of hundreds of French language titles on technology and business topics.

Start learning jQuery, lean management, the latest Adobe programs, and more with over 400 French-language titles (and many more on the way) from Pearson France and Éditions Eyrolles. Continue reading →

With the increasing popularity of Big Data and new demands to store and process large amounts of data, newer technologies are rapidly being developed to meet the needs of developers. There are a number of new database technologies that have emerged recently, which are branded under the umbrella term of NoSQL, which enable databases to achieve unprecedented levels of scalability by forgoing the rigid structure of traditional SQL databases and adopting a more flexible data model. It would not be unfair to say that this NoSQL movement was ignited by the pioneering work of Google engineers in the form of Google BigTable atop of the Google FileSystem. This work is detailed in the paper BigTable: A Distributed Storage System for Structured Data. Since Bigtable is proprietary, it was not available for use for developers in general; not until Apache HBase was born.

HBase is an open source, NoSQL database that is modeled after Google’s BigTable implementation. HBase allows a large amount of data to be stored and processed in the form of very large tables, comprising of billions of rows of data. HBase achieves scalability by distributing the data over a cluster of nodes, and it achieves this distribution by running on top of Apache HDFS (Hadoop Distributed FileSystem) and Hadoop itself. In this article, we will discuss getting started with HBase and briefly cover using the HBase shell to store and retrieve data from the HBase database.
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Bleeding Edge Press, a publisher of short ebooks and videos, focuses on
early or hot topics that ride the pulse of the developer community. Moving
quickly through development, and tapping into decades of publishing
experience, these short ebooks focus on developer-level topics and are
being published in Safari Books Online, allowing subscribers to get their
“hands” on these hot topics. The ebooks will also be published on Amazon,
Google Play and the iBookstore.

Troy Mott, Co-founder and Publisher of Bleeding Edge Press, has benefited
from working closely with Adam Hyde (http://toc.oreilly.com/ahyde),
founder of the Book Sprint methodology (http://www.booksprints.net). “Zero
to book in 5 days. Seem impossible? Its not, its very possible, fun, and extremely
rewarding,” says Adam Hyde. “Book Sprints produce great books and they are a great
learning environment and team-building process.”
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As mentioned in a previous blog post, Entity Framework is an object-relational database mapper that enables easy database access (and CRUD) for .NET developers using domain-specific .NET objects that EF can generate for you. You will be thrilled with how easy it can be to do the same type of database tasks using EF that you previously had to write a lot of code to do. And anything that can make my life easier as a developer is okay by me. But sometimes with all that power things may get a little out of sync and you end up scratching your head wanting to know what went wrong. Continue reading →

Numerous companies are offering solutions to secure mobile devices in the enterprise by supporting a Bring Your Own Device (BYOD) policy inside the government. Yet even the most robust solutions are still unable to protect mobile devices from the large number of cyber threats that they face. This article introduces you to the Open Web Application Security Project (OWASP) Top Ten Risks. You will read about an example of one of these risks, and you will be introduced to a number of resources to help you develop more secure mobile applications.
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