End of relational databases? What is NoSQL?

NoSQL DatabaseV recently increasingly heard about some NoSQL database. What is it? And why are they needed? You might think that the term NoSQL means that SQL is no longer to be used or that the SQL is dead. But, no. In this case, we talk about another. Just today s SQL-database already can not solve all the problems of storage. Therefore NoSQL means - “not only SQL”. In addition to well-established, classical databases, it took us a repository of information, built on different principles.
Relational databases can not cope

What is the reason that relational (SQL) database longer satisfy us? Recently, we can see a trend in the development of four storage technology. The first trend - increasing the amount of stored data. Today the storage reached such epic proportions that it is hard to imagine. Only in 2009 and 2010 in the databases was retained more information than in all previous history. The second trend - the interrelatedness of data. Information is no longer isolated. Each piece of knowledge is somehow related to the data in other repositories of information. Internet sites link to other pages. Tags link labeled information from different sources. Ontologies establish relationships between different terms, etc. etc. The third trend - the use of semistructured information. Learn more about easy database creator.

Take a simple example: the description of the goods in the store. If earlier it was enough 5.6 fields to describe a man’s shirt (size, color, material, product photo, …), but now the number of parameters can be up to several dozen. Moreover, for different shirts will use a different set of parameters. In such circumstances, it becomes extremely difficult to determine in advance the structure of the table that stores the description. The fourth trend - the architect. In the 80′s of last century, the typical architecture used one big computer (mainframe) and one database. In the 90s, the spread was client-server architecture. In the new century are widely used web-services, each with their own backend-ohms (roughly speaking, from its database) and other distributed solutions. It turned out that, in such circumstances, the relational database performance drops sharply. And if the majority of web-sites performance is enough, for applications such as social networks or advanced search services SQL database have failed.