Big Data Analytics is generally used for building models to periodically optimize processes i.e. After-it-Happens business. But this limits the use of Big Data as there is always a delay in the data-to-action cycle and also, the analytical capabilities are limited at the business’s disposal. A better application of big data analytics is using it for As-it-Happens business. It enables us to leverage the data and models moment by moment to make an impact on business operations in real time.

Steve Wooledge, Vice President of Product Marketing at MapR, gives examples of real life applications that leverage a big data environment that integrates OLTP and analytical databases in his following article:

http://www.forbes.com/sites/teradata/2015/04/09/creating-the-as-it-happens-business-analytics-drives-action/

Today's databases should be flexible and should be able to deliver extreme performance and handle humongous data volumes. So database architects have come up with NoSQL, NewSQL alternatives to relational database management systems (RDBMS). In order to choose among these three, there has to be a fundamental understanding of all the three technologies. RDBMS can handle thousands of transactions per second but the new face of online transaction processing (OLTP) in scenarios such as real-time advertising, fraud detection, multi-player games, and risk analysis, to name a few, involves close to a million transactions per second -- a pace that traditional RDBMS has problem in dealing with. These problems can be addressed by NoSQL and NewSQL. NoSQL database management systems store data in a variety of formats. Most NoSQL products discard ACID performance to achieve data storage flexibility. NewSQL, retain both SQL and ACID, but they overcome the performance overhead of RDBMS. In order to choose the type of database the following questions have to be answered-To what extent do you rely on data in terms of storage, processing, and analysis? How important are the scale, flexibility, and performance aspects of a DBMS? What is your level of investment in incumbent technologies? Read more at:

http://www.informationweek.in/informationweek/news-analysis/297462/choose-nosql-newsql-rdbms