Apache Hadoop Pseudo-distributed mode installation helps you to simulate a multi node installation on a single node. Instead of installing hadoop on different servers, you can simulate it on a single server.

Before you continue, make sure you understand the hadoop fundamentals, and have tested the standalone hadoop installation.

If you’ve already completed the 1st three steps mentioned below as part of the standlone hadoop installation, jump to step 4.
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This article explains basics of SQL Injection with an example that shows SQL Injection, and provides methods to prevent from these attacks.

As the name suggests, this attack can be done with SQL queries. Many web developers are unaware of how an attacker can tamper with the SQL queries. SQL-Injection can be done on a web application which doesn’t filter the user inputs properly and trusts whatever the user provides. The idea of SQL injection is to make the application to run undesired SQL queries.
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Suppose a person is driving a car on a highway at a speed of 70 miles per hour. Now, somehow the car meets with an accident. Fortunately the airbag deployed at the right time and saved the life of the driver.

So, we see that airbag is a very good feature in a car which can save a life someday. But, did we think what would have happened if the airbag would have deployed a few seconds late? Yes, we would have lost a life. So just imagine the dependency on the accuracy of opening of the airbag.

So, what makes that airbag deploy at the right time? Well, welcome to the world of RTOS.

RTOS stands for Real time operating systems.
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Oracle VM VirtualBox is an open source virtualization software that you can install on various x86 systems. You can install Oracle VM Virtualbox on top of Windows, Linux, Mac, or Solaris. Once you install the virtualbox, you can create virtual machines that can be used to run guest operating systems like Windows, Linux, Solaris, etc.

On a high-level Oracle VM VirtualBox is similar to VMware. Oracle got this VirtualBox technology from Sun.

This article cover the basic installation of virtualbox and how to install a guest OS on it.
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When you implement Apache Hadoop in production environment, you’ll need multiple server nodes. If you are just exploring the distributed computing, you might want to play around with Hadoop by installing it on a single node.

This article explains how to setup and configure a single node standalone Hadoop environment. Please note that you can also simulate a multi node Hadoop installation on a single server using pseudo distributed hadoop installation, which we’ll be covering in detail in the next article of this series. (next article: How To Install Apache Hadoop Pseudo Distributed Mode on a Single Node)
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Even though Perl 5.10 is an old release, there are few things that was introduced in Perl 5.10, which you might find it useful.

In the future article of this series, we’ll be covering new features of Perl 5.14

These are the 5 new Perl 5.10 features that you might find helpful.
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In C programming language, the concept of pointers is the most powerful concept that makes C stand apart from other programming languages. In the part-I of this series we discussed the fundamental concepts around C pointers.

In this article, we will try to develop understanding of some of the relatively complex concepts. The following are explained in this article with examples:

1. Constant pointer and pointer to constant.
2. Pointer to pointer with an example
3. Array of pointers with an example
4. Pointer to functions with an example

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