Re: default_text_search_config and expression indexes

Oleg Bartunov <oleg@sai.msu.su>

From: Oleg Bartunov <oleg@sai.msu.su>
To: Alvaro Herrera <alvherre@commandprompt.com>
Cc: tomas@tuxteam.de, Bruce Momjian <bruce@momjian.us>, Heikki Linnakangas <heikki@enterprisedb.com>, Ron Mayer <rm_pg@cheapcomplexdevices.com>, pgsql-hackers@postgresql.org
Date: 2007-08-15T04:33:16Z
Lists: pgsql-hackers
On Tue, 14 Aug 2007, Alvaro Herrera wrote:

> Oleg Bartunov wrote:
>> On Tue, 14 Aug 2007, Alvaro Herrera wrote:
>>
>>> Oleg Bartunov wrote:
>>>> On Thu, 9 Aug 2007, tomas@tuxteam.de wrote:
>>>>
>>>>> Maybe I'm missing something, but it seems to me that the configuration
>>>>> is more attached to a column/index thatn to the whole database. If
>>>>> there's a default in an expression, I'd rather expect this default to be
>>>>> drawn from the index involved than from a global value (like a
>>>>> functional
>>>>> index does now).
>>>>
>>>> I'm tired to repeat - index itself doesn't know about configuration !
>>>
>>> Is there a way to change that?  For example store the configuration in a
>>> metapage or something?
>>
>> it's useless, in general, since you could use different configuration to
>> build tsvector.
>
> Hmm, sorry, I think I just understood what this was about: so you mean
> that the configuration is really *per row* and not per index?  So I can

in the very extreme case, yes. Index doesn't care about configuration.
Everything should works without index !

> store rows into an index using more than one configuration, and it will
> work?

why not. For one set of documents you can use one configuration
(parser+mappings), for another - different configuration.


 	Regards,
 		Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83