Re: contrib\xml2 package's xpath_table function in PostgreSQL

Hi,

We have a huge system based on PostgreSQL with xml2 functions. From the PostgreSQL 8.4 documentation F.38.1. Deprecation notice, it looks like those functions are removed. However, our solution is very huge, and heavily depends on them.

1. Could you please give me some instructions to get them back in the PostgreSQL 8.4?

2. Could you please also give me some details if we can find similar functions we can use to replace them in PostgreSQL 8.4?

Thank you in advance.

Best,
Michael

PS. Attached copied from PostgreSQL 8.4 documentation:
================================

F.38. xml2

The xml2 module provides XPath querying and XSLT functionality.

F.38.1. Deprecation notice

From PostgreSQL 8.3 on, there is XML-related functionality based on the SQL/XML standard in the core server. That functionality covers XML syntax checking and XPath queries, which is what this module does, and more, but the API is not at all compatible. It is planned that this module will be removed in PostgreSQL 8.4 in favor of the newer standard API, so you are encouraged to try converting your applications. If you find that some of the functionality of this module is not available in an adequate form with the newer API, please explain your issue to pgsql-hackers(at)postgresql(dot)org so that the deficiency can be addressed.

On Sun, Jan 31, 2010 at 4:00 PM, HX Zheng <hx_zheng(at)hotmail(dot)com> wrote:
> We have a huge system based on PostgreSQL with xml2 functions. From the
> PostgreSQL 8.4 documentation F.38.1. Deprecation notice, it looks like those
> functions are removed. However, our solution is very huge, and heavily
> depends on them.

The functions haven't actually been removed in 8.4, in spite of the
deprecation notice. But it's very easy to use them in a way that
crashes the entire server, so you're playing with fire. :-(

...Robert

Is there a way to fix it so that those functions are usable in 8.4 without
crashing the server?

Thanks,
M Z

On Mon, Feb 1, 2010 at 10:50 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> The functions haven't actually been removed in 8.4, in spite of the
> deprecation notice. But it's very easy to use them in a way that
> crashes the entire server, so you're playing with fire. :-(
>
> ...Robert
>
> --
> Sent via pgsql-hackers mailing list (pgsql-hackers(at)postgresql(dot)org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-hackers
>

On Mon, Feb 1, 2010 at 1:20 PM, M Z <jm80008(at)gmail(dot)com> wrote:
> Is there a way to fix it so that those functions are usable in 8.4 without
> crashing the server?

Nobody seems to be interested enough to figure that out and submit a
patch to fix it. If someone does, I think it would have a good chance
of being accepted.

...Robert

I am very interested in doing it. However I am new to postgresql. Could you
and anyone here please give me some hint, which way I should, which part of
code I should focus to fix it?

Thanks,
M Z

On Mon, Feb 1, 2010 at 1:23 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> On Mon, Feb 1, 2010 at 1:20 PM, M Z <jm80008(at)gmail(dot)com> wrote:
> > Is there a way to fix it so that those functions are usable in 8.4
> without
> > crashing the server?
>
> Nobody seems to be interested enough to figure that out and submit a
> patch to fix it. If someone does, I think it would have a good chance
> of being accepted.
>
> ...Robert
>