Re: [HACKERS] Re: [HACKERS] XQuery or XPathサポート

Is there any plan for supporting XQuery or XPath in 8.3?
--
Tatsuo Ishii
SRA OSS, Inc. Japan

On 3/5/07, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:
> Is there any plan for supporting XQuery or XPath in 8.3?

I've submitted patch for simple XPath 1.0 support (based on libxml2):
http://archives.postgresql.org/pgsql-patches/2007-03/msg00088.php

This function does XML parsing at query time. So, you should use
functional indexes over this function to reach good perfromance.

My curent plans include development of additional contrib module for
alternative (experimental), efficient support of XPath (no XML parsing
at query time), similar to Microsoft's ORDPATHs. This project is
called "xlabel" and I hope to implement its prototype soon.

--
Best regards,
Nikolay

From: "Nikolay Samokhvalov" <samokhvalov(at)gmail(dot)com>
Subject: [HACKERS] Re: [HACKERS] XQuery or XPathサポート
Date: Mon, 5 Mar 2007 14:51:43 +0300
Message-ID: <e431ff4c0703050351v781c5602hfc0c6c9976b6b139(at)mail(dot)gmail(dot)com>

> On 3/5/07, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:
> > Is there any plan for supporting XQuery or XPath in 8.3?
>
> I've submitted patch for simple XPath 1.0 support (based on libxml2):
> http://archives.postgresql.org/pgsql-patches/2007-03/msg00088.php

But contrib/README.xml2 stated:

"This version of the XML functions provides both XPath querying and
XSLT functionality"

What's the difference between yours and contrib/xml2?

> This function does XML parsing at query time. So, you should use
> functional indexes over this function to reach good perfromance.
>
> My curent plans include development of additional contrib module for
> alternative (experimental), efficient support of XPath (no XML parsing
> at query time), similar to Microsoft's ORDPATHs. This project is
> called "xlabel" and I hope to implement its prototype soon.

Also Peter seems to add xml datatype to 8.3. Does your functuion
handle this data type?
--
Tatsuo Ishii
SRA OSS, Inc. Japan

On 3/5/07, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:
> From: "Nikolay Samokhvalov" <samokhvalov(at)gmail(dot)com>
> > I've submitted patch for simple XPath 1.0 support (based on libxml2):
> > http://archives.postgresql.org/pgsql-patches/2007-03/msg00088.php
>
> But contrib/README.xml2 stated:
>
> "This version of the XML functions provides both XPath querying and
> XSLT functionality"
>
> What's the difference between yours and contrib/xml2?

"Mine" is supposed to go to the core. And, contrib/xml2 contains less
"semantically clear" functions, that were developed for practical
purposes (e.g. xml_number() returns only one, first number from the
suquence).

>
> > This function does XML parsing at query time. So, you should use
> > functional indexes over this function to reach good perfromance.
> >
> > My curent plans include development of additional contrib module for
> > alternative (experimental), efficient support of XPath (no XML parsing
> > at query time), similar to Microsoft's ORDPATHs. This project is
> > called "xlabel" and I hope to implement its prototype soon.
>
> Also Peter seems to add xml datatype to 8.3. Does your functuion
> handle this data type?

Of course. Peter's patches are partially based on the result of my
SoC2006 work ("Initial XML support for PostgreSQL"). XPath patch was
discussed with him and in -hackers, now I'm waiting for its review.

--
Best regards,
Nikolay

> On 3/5/07, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:
> > From: "Nikolay Samokhvalov" <samokhvalov(at)gmail(dot)com>
> > > I've submitted patch for simple XPath 1.0 support (based on libxml2):
> > > http://archives.postgresql.org/pgsql-patches/2007-03/msg00088.php
> >
> > But contrib/README.xml2 stated:
> >
> > "This version of the XML functions provides both XPath querying and
> > XSLT functionality"
> >
> > What's the difference between yours and contrib/xml2?
>
> "Mine" is supposed to go to the core. And, contrib/xml2 contains less
> "semantically clear" functions, that were developed for practical
> purposes (e.g. xml_number() returns only one, first number from the
> suquence).

I see.

> > > This function does XML parsing at query time. So, you should use
> > > functional indexes over this function to reach good perfromance.
> > >
> > > My curent plans include development of additional contrib module for
> > > alternative (experimental), efficient support of XPath (no XML parsing
> > > at query time), similar to Microsoft's ORDPATHs. This project is
> > > called "xlabel" and I hope to implement its prototype soon.
> >
> > Also Peter seems to add xml datatype to 8.3. Does your functuion
> > handle this data type?
>
> Of course. Peter's patches are partially based on the result of my
> SoC2006 work ("Initial XML support for PostgreSQL"). XPath patch was
> discussed with him and in -hackers, now I'm waiting for its review.

The XPath support is 1.0 or 2.0?
--
Tatsuo Ishii
SRA OSS, Inc. Japan

On 3/5/07, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:
> The XPath support is 1.0 or 2.0?

1.0

--
Best regards,
Nikolay