Re: No documentation for filtering dictionary feature?

There's an entry in the 9.0 release notes saying that we've got
filtering dictionaries now. Cool, but I don't see any documentation
of the feature in textsearch.sgml. Shouldn't there be some?

regards, tom lane

On Tue, 24 Aug 2010, Tom Lane wrote:

> There's an entry in the 9.0 release notes saying that we've got
> filtering dictionaries now. Cool, but I don't see any documentation
> of the feature in textsearch.sgml. Shouldn't there be some?

Something like
http://developer.postgresql.org/pgdocs/postgres/unaccent.html ?
Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83

Oleg Bartunov <oleg(at)sai(dot)msu(dot)su> writes:
> On Tue, 24 Aug 2010, Tom Lane wrote:
>> There's an entry in the 9.0 release notes saying that we've got
>> filtering dictionaries now. Cool, but I don't see any documentation
>> of the feature in textsearch.sgml. Shouldn't there be some?

> Something like
> http://developer.postgresql.org/pgdocs/postgres/unaccent.html ?

No --- that's documentation for a specific contrib module, not
documentation about the feature in general. Currently the general
description of dictionaries says that it's impossible for a dictionary
to modify the input lexeme. Clearly that needs some adjustment,
but I'm not sure what, because the feature is not explained anywhere ;-)

regards, tom lane

On Wed, 25 Aug 2010, Tom Lane wrote:

> Oleg Bartunov <oleg(at)sai(dot)msu(dot)su> writes:
>> On Tue, 24 Aug 2010, Tom Lane wrote:
>>> There's an entry in the 9.0 release notes saying that we've got
>>> filtering dictionaries now. Cool, but I don't see any documentation
>>> of the feature in textsearch.sgml. Shouldn't there be some?
>
>> Something like
>> http://developer.postgresql.org/pgdocs/postgres/unaccent.html ?
>
> No --- that's documentation for a specific contrib module, not
> documentation about the feature in general. Currently the general
> description of dictionaries says that it's impossible for a dictionary
> to modify the input lexeme. Clearly that needs some adjustment,
> but I'm not sure what, because the feature is not explained anywhere ;-)

Well, http://www.pgcon.org/2009/schedule/attachments/92_2009.pdf contains
description of Dictionary API and new TSLexeme->flags: TSL_FILTER
If dictionary returns only one lexeme with TSL_FILTER flag, then that
lexeme will be used as an input for the subsequent dictionaries in the chain.

I'm not sure, how to incorporate this into current documentation, since there
is no built-in filtering dictionary. Probably, it'd be nice to add filtering option
to simple dictionary to illustrate this feature.

Unfortunately, I'm busy-busy :(

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

Oleg Bartunov <oleg(at)sai(dot)msu(dot)su> writes:
> On Wed, 25 Aug 2010, Tom Lane wrote:
>> No --- that's documentation for a specific contrib module, not
>> documentation about the feature in general. Currently the general
>> description of dictionaries says that it's impossible for a dictionary
>> to modify the input lexeme. Clearly that needs some adjustment,
>> but I'm not sure what, because the feature is not explained anywhere ;-)

> Well, http://www.pgcon.org/2009/schedule/attachments/92_2009.pdf contains
> description of Dictionary API and new TSLexeme->flags: TSL_FILTER
> If dictionary returns only one lexeme with TSL_FILTER flag, then that
> lexeme will be used as an input for the subsequent dictionaries in the chain.

OK. I'll see what can be done with the docs.

regards, tom lane