Databases Reference
In-Depth Information
CHAPTER
4
More Advanced Applications
Databases and related applications no longer only deal with alphanumeric records. They contain
several kinds of heterogeneous data distributed in multiple sources. The same is true for the devices
used to access them that are not just desktop computers but are becoming more and more mobile
and ubiquitous.
4.1
WEB DATA
As in so many areas, the web is changing the nature of data access. For some application areas it
is a relatively small change: SQL databases are used to drive web interfaces instead of client-server
applications and may be hosted on the cloud. There are changes in practices because web user
interfaces are different from desktop ones, but this is not fundamentally about the data.
However, there are also more fundamental changes: data that were once in government or
corporate databases are made publically available, user-generated content proliferates, mashups in-
tegrate, and the semantic web seeks to link all the world's data. This is, perhaps, not surprising as
the world-wide web was developed precisely as a means of distributing data.
4.1.1 THE CHANGING FACE OF THE WEB
The web is now a place to meet friends, browse news, book holidays, or find read information. How-
ever, the world-wide web was originally designed for sharing the data of CERN (
Berners-Lee, T.
,
1999
), and it has become a critical part of many organizations information systems.
The web has evolved continuously since the early 1990s, but it can be seen in terms of three
phases, each with very different kinds of data (described in more detail in the next Section
4.1.2
):
First Generation Web
- The first generation web (sometimes called web1.0) is characterized
by familiar HTML pages and links. This first generation web gave rise to early home-made web
pages, but it became quickly dominated by traditional 'publishing' models, with the majority of the
volume of viewed content being produced by a small number of large companies. The data of this
first generation web was mostly focused at human consumption: images, text, occasionally sound,
and movies, although often scientific and technical data are also available as downloadable files it
tends to sit at the 'edge' of the web, not an interlinked part of it. More structured data were there, in
the form of databases for eCommerce and other back-end data, but this was largely invisible behind
web user interfaces.
Second GenerationWeb (web2.0)
- The term web2.0 was popularized in 2005 by Tim O'Reilly's
article “What Is Web 2.0” (
O'Reilly, T.
,
2005
) and the founding of the web2.0 conference. The term
