SQL SERVER – What is Cloud Computing – Introduction to Cloud Computing

What is cloud computing, in words a database person can actually use? That is the question I want to answer here in plain language, followed by a short list of things I would check before putting any SQL Server data in the cloud.

The simple version: cloud computing means using servers, storage, databases or whole applications that live in someone else’s data center, and reaching them over the Internet. Network diagrams have drawn the Internet as a cloud for a long time, which is where the name comes from. You use what you need, for as long as you need it, and the provider looks after the hardware underneath.

What makes it more than renting a server is that it stretches. You can add capacity when demand goes up and hand it back when demand drops, and you usually pay for what you actually use. A mail or office suite that runs in your browser is the everyday example.

Three ways to use the cloud

• Software as a Service (SaaS): you use a finished application in the browser, and the provider runs everything behind it.
• Platform as a Service (PaaS): you get a managed platform, such as a hosted database, and you bring your own data and code.
• Infrastructure as a Service (IaaS): you rent virtual machines, storage and networking, and you install and manage the software yourself, SQL Server included.

What I would check before moving a database

• Where will the data physically live, and does that meet the rules your company or your country has for that kind of data?
• Who at the provider can reach the data, and how is it kept separate from other customers on the same hardware?
• How do backups and restores work, and what happens during an outage? Ask about disaster recovery before you need it.
• How far is the application from the database? Network delay between the two can hurt an application that makes many small calls.
• How does the bill grow as usage grows, and how would you get your data out if you ever decide to leave?

Notice that none of these questions go away just because the hardware does. You still own your data, your logins and permissions, and the speed of your queries. I also wrote a longer introduction that walks through the architecture, the different forms of cloud computing and the main concerns.

Published by Pinal Dave on SQLAuthority. More of my work at pinaldave.com.