is there an "xml-include"

Leigh Dodds ldodds at INGENTA.COM
Wed Nov 21 09:15:02 CET 2001

At risk of distracting from the discussion at hand:

> If you feel that descriptive data can only be modeled with
> relations, then you can never get XML to work for you.  It is not
relational, it is strictly
> hierarcical. It does not and, by design, cannot support the relational
model.  Do not
> confuse XML with a database.  It is -not- designed to be a database.  The
few databases that
> use XML are all hierarcical XML is designed to model the structure of
> documents.  If you want to create a database, use a database
> language. XML is what you use in the report.

Well strictly speaking XML can be used to model/serialise graph structures,
so while it is hierarchical, and the syntax does require a single root,
no reason why this can't become a graph (or other) structure once parsed.

There's been a lot of activity (unsurprisingly) in serialising XML into and
out of databases. In general it's not an easy problem to solve, but it
can be done.

Also, I'd have to disagree with the statement that 'the few databases
that use XML are all hierarchical'. Current XML-aware databases fall into
two categories: XML-Enabled Databases (i.e. relational databases that
have added XML features) and Native XML Databases (i.e. those specifically
designed to store XML). Databases in the first category do tend to be
primarily relational in nature. Those in the second are a mixture: they
the XML document internally, and this might be achieved using a relational



Leigh Dodds, Research Group, Ingenta | "Pluralitas non est ponenda |    sine necessitate"    |     -- William of Ockham

More information about the tdwg-content mailing list