| From: | Simon Riggs <simon(at)2ndQuadrant(dot)com> |
|---|---|
| To: | Andrew Dunstan <andrew(at)dunslane(dot)net> |
| Cc: | Hannu Krosing <hannu(at)2ndQuadrant(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Peter Eisentraut <peter_e(at)gmx(dot)net>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>, Nikolay Samokhvalov <samokhvalov(at)gmail(dot)com> |
| Subject: | Re: xpath processing brain dead |
| Date: | 2009-03-02 09:05:37 |
| Message-ID: | 1235984737.16176.780.camel@ebony.2ndQuadrant |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Sun, 2009-03-01 at 18:22 -0500, Andrew Dunstan wrote:
> I think the XML type needs to conform to the SQL/XML spec. However, we
> are trying to apply XPath, which has a different data model, to that
> type - hence the impedance mismatch.
>
> I think that the best we can do (for 8.4, having fixed 8.3 as best we
> can without adversely changing behaviour) is to throw the
> responsibility
> for ensuring that the XML passed to the function is an XML document
> back on the programmer. Anything else, especially any mangling of the
> XPath
> expression, presents a very real danger of breaking on correct input.
Can we provide a single function to bridge the gap between fragment and
document? It will be clearer to do this than to see various forms of
appending/munging, even if that function is a simple wrapper around an
append.
--
Simon Riggs www.2ndQuadrant.com
PostgreSQL Training, Services and Support
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Andrew Dunstan | 2009-03-02 12:48:24 | Re: xpath processing brain dead |
| Previous Message | Heikki Linnakangas | 2009-03-02 08:37:03 | Re: a proposal for an extendable deparser |