Re: [REVIEW] Re: Fix xpath() to return namespace definitions

2014-12-14 22:18 GMT+07:00 Ali Akbar <the(dot)apaan(at)gmail(dot)com>:
>
>
> I ran a test using postgres-US.fo built in the PostgreSQL source tree,
>> which is 38 MB, and ran
>>
>> select unnest(xpath('//fo:bookmark-title', b, array[array['fo',
>> 'http://www.w3.org/1999/XSL/Format']])) from data;
>>
>> (Table contains one row only.)
>>
>> The timings were basically indistinguishable between the three code
>> versions.
>>
>> I'll try to reproduce your test. How big is your file? Do you have a
>> link to the actual file? Could you share your load script?
>>
>
> I use this xml sample:
> http://w3.energistics.org/schema/prodml_v1.2.0_data/XML_Examples/productVolume_no_xsl.xml
>
> Basically i loaded the xml to table u 100 times. Load script attached.
>

Peter, while reviewing the better performing patch myself, now i think the
patch needs more work to be committed. The structuring of the method will
be confusing in the long term. I think i'll restructure the patch in the
next commitfest.

So i propose to break the patch:
1. We apply the current patch which uses xmlNodeCopy, so that the
long-standing bug will be fixed in postgres.
2. I'll work with the performance enhancement in the next commitfest.

Maybe for (2), the current better-performing patch can be viewed as PoC of
the expected performance.

Regards,
--
Ali Akbar