Microsoft DocumentDB is Generally Available

Below is a link to the announcement.

http://azure.microsoft.com/blog/2015/04/08/nosql-database-service-azure-documentdb-now-generally-available/

NoSQL databases are getting a lot of traction. Microsoft just released DocumentDB. One of the key differences is data added to DocumentDB is automatically indexed. Traditional NoSQL databases offer little to no indexing and severely limit your ability to query data. NoSQL database tend to be very fast and scale well to large data. Nearly all “Big Data” implementations are in a NoSQL database.

From Wikipedia, “A NoSQL or Not Only SQL database provides a mechanism
for storage and retrieval of data that is modelled in means other than
the tabular relations used in relational databases.”

Here are a couple examples with alternative to relational database solutions can be used.

1. Relational databases typically receive data and distribute it among multiple tables then triggers fire and indexes are updated. NoSQL databases tend to accept the data in whatever for it is in, usually JSON, and just saves it. If you have an application that receives orders you could save the order directly to a NoSQL database and return control back to the user. Immediately backend processes start and merge the new NoSQL database record into your relational database.
2. Storing images is another strength of NoSQL type databases. There are many flavours of these databases and each is geared to perform well in a given scenario. “Azure Storage Blob service” isn’t a file directory but not really a database either but it is a data store of sorts.

Nicely summarized article on NoSQL
https://www.devbridge.com/articles/benefits-nosql/