Re: [xml-dev] XML-enabled databases, XQuery APIs

[Ronald Bourret <rpbourret@rpbourret.com>]

I'm neutral here, but for an opposing view see "XML Parsing: A Threat to 
Database Performance" [1] by Matthias Nicola of IBM. From the abstract:

"XML parsing is generally known to have poor performance characteristics 
relative to transactional database processing. Yet, its potentially 
fatal impact on overall database performance is being underestimated. We 
report real-word database applications where XML parsing performance is 
a key obstacle to a successful XML deployment..."

-- Ron

[1] 
http://lists.w3.org/Archives/Public/www-ws/2004Oct/att-0032/MNicola_CIKM_2003_1_.pdf

Michael Kay wrote:
> I would be very surprised if XML parsing contributes anything noticeable to
> the cost of a database load (in shredding mode). Except possibly for a
> pathological XML document containing 3 nodes and 3 billion bytes.
> 
> I haven't looked at the latest products from MS or Oracle, but my experience
> of database loading with complex data and a realistic level of indexing is
> that it's a couple of orders of magnitude slower than XML parsing. You can
> improve that with a custom loader that bypasses SQL and does a lot of
> heavy-duty sorting and merging to minimize head movement on the disk (does
> anyone still do that?), but I think it's still true that the parsing cost is
> immaterial.