Database Reference
In-Depth Information
Chapter 3
Cloud-Hosted Data Storage Systems
Over the past decade, rapidly growing Internet-based services such as e-mail,
blogging, social networking, search and e-commerce have substantially redefined
the way consumers communicate, access contents, share information and purchase
products. Relational database management systems (RDBMS) have been considered
as the
one-size-fits-all
solution for data persistence and retrieval for decades.
However, ever increasing need for scalability and new application requirements
have created new challenges for traditional RDBMS. Recently, a new generation
of low-cost, high-performance database software, aptly named as
NoSQL
(Not Only
SQL), has emerged to challenge the dominance of RDBMS. The main features of
these systems include: ability to horizontally scale, supporting weaker consistency
models, using flexible schemas and data models and supporting simple low-level
query interfaces. In this chapter, we explore the recent advancements and the state-
of-the-art of Web scale data management approaches. We discuss the advantages
and the disadvantages of several recently introduced approaches and its suitability
to support certain class of applications and end-users.
3.1
Introduction
The recent advances in the Web technology has made it easy for any user to
provide and consume content of any form. For example, we buy topics on
Amazon
,
sell thing on
eBay
, stay in contact with friends and colleagues via
Facebook
and
Linkedin
, start a blog using
Wo rd P re s s
or
LiveJournal
, share pictures via
Picasa
or
Flickr
, and share and comment on videos via
YouTube
. These are just examples to
name a few well-known internet-based services that we use in our everyday life.
Arguably, the main goal of the next wave is to facilitate the job of implementing
every application as a distributed, scalable and widely-accessible service on the
Web like these example services. In practice, common features of these applications
include that they are both
data-intensive
and very
interactive
applications. For
example, the Facebook social network has announced that it has more than a
