Databases Reference
In-Depth Information
Figure 4.7:
OpenStreetMap - end user adding a feature.
This self-describing nature has meant that XML has been adopted widely on the web not
just as a text mark-up notation but as, effectively, a data serialization. For example, Figure
4.8
shows
XML being used to package together information about this topic. XML has several problems when
used in this way. Some are trivial yet serious, such as the lack of a standard way to include a tab
character in XML data. Others are more subtle, such as the confusion between slot/variable name
and type.
<book>
<name>User-Centered Data Management</name>
<author>Tiziana Catarci</author>
<author>Stephen Kimani</author>
<author>Giuseppe Santucci</author>
<author>Alan Dix</author>
</book>
Figure 4.8:
Describing this topic in XML.
There has been significant work on the use of XML in databases; however, the greatest use has
been either as a data transfer format between web services, invisible to the user, or as an intermediate
format in web systems with a multi-tier (also known as n-tier) architecture. In these multi-tier
