On Mon, 2009-03-02 at 15:25 +0200, Peter Eisentraut wrote:
> Hannu Krosing wrote:
> > Is it just that in you _can't_ use Xpath on fragments, and you _need_ to
> > pass full documents to Xpath ?
> >
> > At least this is my reading of Xpath standard.
>
> It is easy to read the XPath standard that way, because the concept of
> fragments is not defined outside of SQL/XML, and is therefore unknown to
> the XPath standard.
How is the opposite - Does SQL/XML specify Xpath usage for XML(SEQUENCE)
and XML(CONTENT) ?
> The question at hand is rather whether we can
> usefully adapt it.
This sounds like trying to adapt integer arithmetic to
lists-of-integers.
Even for simple things like addition, there are several ways of doing it
[1,2,3] + [1,1,1] = [1,2,3,1,1,1]
[1,2,3] + [1,1,1] = [2,3,4]
[1,2,3] + [1,1,1] = [[1,2,3],[1,1,1]]
all seem possible and "logical"
--
Hannu Krosing http://www.2ndQuadrant.com
PostgreSQL Scalability and Availability Services, Consulting and Training