New Page 2

For an example of the virtues of semi-structured data, consider the following document:

<game>

<name>

<american>Soccar</american>

<british>Football</british>

</name>

</game>

<game>

<name>Basketball</name>

</game>

...

This is superior to unstructured representations because:

Hierarchy is preserved

Some structured information is present

It is superior to structured representations because:

	Relaxed schema -- not all records must contain the same information
	Hierarchy is preserved, whereas it is generally flattened in a relational system

Given these advantages, researchers in the database community have been working to develop specialized databases that are optimized for storing and querying semi-structured data...

Please move on to XML Database engines.

Last updated: May 01, 2002.