Page 63 - Building Big Data Applications

Chapter 2 Infrastructure and technology 57

FIGURE 2.18 Sqoop2 architecture.

FIGURE 2.19 HCatalog concept. Image original sourcedHortonWorks.

NoSQL

Relational databases cannot handle the scalability requirements of large volumes of
transactional data, and often fail when trying to scale up and scale out. The vendors of
the RDBMS-based technologies have tried hard to address the scalability problem by
replication, distributed processing and many other models, but the relational architec-
ture and the ACID properties of the RDBMS have been a hindrance in accomplishing the
performance requirements of applications such as sensor networks, web applications
and trading platforms, and much more. In the late 1980s there were a number of
research papers that were published about newer models of SQL databases, but not
based on ACID requirements and the Relational model. Fast forward to 1998, the
emergence of a new class of databases that can support the requirements of high-speed