Jean-Michel,
> As this is an XML related question and XML is quite new, I am posting
> on hackers ML. If any solution is being developped, please inform us.
How is it XML-related?
> We would like to develop a free REST database (real-estate standard)
> based on a PostgreSQL schema. This is a free solution for free data
> also, released under BSD or GPL license. We are charity.
>
> This is supposed to a "killer application", so we need to drive down
> queries to 3ms to 5ms to allow hundreds of simultaneous queries.
Well, anything based on XML data is going to be pretty slow. There's just no
way to extra data from an XML field without lots of parsing. I'd tend to
think it would be much faster to store the data conventially, and just
generate XML in response to requests ... either inside or outside PostgreSQL.
Of course, I'd need a lot more detail to make a serious assessment.
Mind you, we'd be thrilled to have you implement a special XML index type. I
don't think it's going to solve your problem, though.
--
Josh Berkus
PostgreSQL @ Sun
San Francisco