An HDFS Tutorial for Data Analysts Stuck With Relational Databases

Introduction

By now, you have probably heard of the Hadoop Distributed File System (HDFS), especially if you are data analyst or someone who is responsible for moving data from one system to another. However, what are the benefits that HDFS has over relational databases?

HDFS is a scalable, open source solution for storing and processing large volumes of data. HDFS has been proven to be reliable and efficient across many modern data centers.

HDFS utilizes commodity hardware along with open source software to reduce the overall cost per byte of storage.

With its built-in replication and resilience to disk failures, HDFS is an ideal system for storing and processing data for analytics. It does not require the underpinnings and overhead to support transaction atomicity, consistency, isolation, and durability (ACID) as is necessary with traditional relational database systems.

Moreover, when compared with enterprise and commercial databases, such as Oracle, utilizing Hadoop as the analytics platform avoids any extra licensing costs.

One of the questions many people ask when first learning about HDFS is: How do I get my existing data into the HDFS?

In this article, we will examine how to import data from a PostgreSQL database into HDFS. We will use Apache Sqoop, which is currently the most efficient, open source solution to transfer data between HDFS and relational database systems. Apache Sqoop is designed to bulk-load data from a relational database to the HDFS (import) and to bulk-write data from the HDFS to a relational database (export).

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Hosting For Freelance Developers: PaaS, VPS, Cloud, And More

At a glance, the hosting industry may not appear exciting, but it’s grunts in data centres the world over that keep our industry going. They are, quite literally, the backbone of the Internet, and as such they make everything possible: from e-commerce sites, to smart mobile apps for our latest toys. The heavy lifting is done in boring data centres, not on our flashy smartphones and wafer thin notebooks.

Whether you’re creating a virtual storefront, deploying an app, or simply doing some third-party testing and development, chances are you need some server muscle. The good news is that there is a lot to choose from. The hosting industry may not be loud or exciting, but it never sleeps; it’s a dog eat dog world, with cutthroat pricing, a lot of innovation behind the scenes, and cyclical hardware updates. Cloud, IaaS and PaaS have changed the way many developers and businesses operate, and these are relatively recent innovations.

In this post I will look at some hosting basics from the perspective of a freelance developer: what to choose and what to stay away from. Why did I underline freelance software engineers? Well, because many need their own dev environment, while at the same time working with various clients. Unfortunately, this also means that they usually have no say when it comes to deployment. For example, it’s the client’s decision how and where a particular web app will be hosted, and a freelancer hired on short-term basis usually has no say in the decision. This is a management issue, so I will not address it in this post other than to say that even freelancers need to be aware of options out there. Their hands may be tied, but in some cases clients will ask for their input and software engineers should help them make an informed decision. Earlier this week, we covered one way of blurring the line between development and operations: DevOps. In case you missed that post, I urge you to check it out and see why DevOps integration can have an impact on hosting as well.

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How Can I Transfer My Domain from one registrar to another?

This article is a complete guide on how to transfer a domain from one registrar to another and will cover the following information:

  1. What to Do Before Transferring Your Domain
  2. How to Begin Your Domain Transfer
  3. How to Ensure Your Transfer is Uninterrupted
  4. Check Your Transfer Status
  5. Troubleshooting a Failed Transfer

What to Do Before Transferring Your Domain

There are several blocks in place to protect your domain name ownership that can cause difficulty in transferring your domain to a new registrar. Before you transfer your domain, it is essential that you ensure that the domain is ready to be transferred. Please go through below pre transfer checklist for preparing a domain for transfer: Continue reading

Step by Step to Change website hosting without downtime

Switching to a new host can be a complicated process. Follow our steps to ensure that your move is smooth and painless

  1. The first step is to join your new host. Make sure to NOT cancel with your old hosting provider, and do not tell them you will be canceling. Keep this a secret from your old host, or they could prematurely terminate your site and cause downtime.
  2. At this point, you should have hosting accounts with two hosting providers (the old and the new one). You will now migrate your entire site from the old host to the new one. This can be done by connecting to the old host’s FTP and downloading all your files, and then by connecting to the new host’s FTP and uploading all your files (maintain the same file and folder structure).
  3. You must also backup any databases on the old host (contact the old host for instructions) and upload the backup files to the new host via FTP. You must then restore your databases from those backup files; this can be done via SSH or cPanel’s phpMyAdmin. Emails do not normally transfer, but you can archive your emails from the old host. You can accomplish this by making a POP3 connection to each email address; this way all the old emails are downloaded to your local computer. The new host will not have those old emails, but the new host will be able to get new emails.
  4. After you have all your files on both hosting accounts, it is time to change your domain name’s DNS. Your new host will provide you with the correct name servers (DNS). You may need to contact the new host to find out what DNS settings you will use for your domain name.DNS name servers usually looks like this (replace “yourhostname.com” with your host’s actual domain name):
    yourhostname.com
    ns2.yourhostname.com

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