by Angela Guess
A recent article provides some basic information about NoSQL databases and their benefits. The article begins, “SQL (for Structured Query Language) has been around for decades and has plenty of benefits. It’s great for centrally managed database schemas, easy ad hoc queries, and data that can be indexed and normalized. There are lots of integrated SQL development environments, reporting tools, and ways to extract, import and transform SQL databases, and SQL has been taught to thousands of software engineers. Most SQL databases can easily run on common Intel hardware with RAM and disk storage in reasonable amounts (250 GB and 1 TB, respectively, are about right).”
It goes on, “SQL also has its limits, especially when you consider how modern Web apps are built. They have to perform and scale well, and handle large collections of documents and odd kinds of data — and none of that plays to SQL’s strengths… This is where NoSQL plays well. It can scale up quickly, can work well with the Web and other online programming environments, and can be made fault-tolerant and more flexible to anticipate needs to change your database schema or repartition your data.”
The article continues, “A good example is the set of databases behind the Twitter service. Twitter users generate more than 12 TB of data every day. Even if Twitter used the fastest disk drives, it would take more than 40 hours to record this information. The company ended up using Hadoop, a distributed file system with automatic replication and fault tolerance. (Visa also used Hadoop in the scenario discussed above, and Yahoo has a 4,000 node-Hadoop cluster.) Hadoop allows Twitter to distribute the load involved in writing all these Tweets across a lot of inexpensive servers.”
photo credit: test.ical.ly
