Re: Creating an index-type for LIKE '%value%'

From: Oleg Bartunov <oleg(at)sai(dot)msu(dot)su>
To: Larry Rosenman <ler(at)lerctr(dot)org>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Creating an index-type for LIKE '%value%'
Date: 2005-02-08 17:17:42
Message-ID: Pine.GSO.4.62.0502082016170.2906@ra.sai.msu.su
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

On Tue, 8 Feb 2005, Larry Rosenman wrote:

> Oleg Bartunov wrote:
>> On Tue, 8 Feb 2005, Larry Rosenman wrote:
>>
>>> Oleg Bartunov wrote:
>>>> On Tue, 8 Feb 2005, Larry Rosenman wrote:
>>>>
>>>>>
>>>>> It doesn't seem to like pieces with hyphens ('-') in the name, when
>>>>> I try To update blacklist set new_domain_lt=text2ltree(domain) I
>>>>> get a Syntax error (apparently for the hyphens).
>>>>>
>>>>
>>>> Try change definition of ISALNUM on ltree.h
>>>>
>>>> #define ISALNUM(x) ( isalnum((unsigned char)(x)) || (x) == '_'
>>>> )
>>>>
>>>> this was already discussed
>>>> http://www.pgsql.ru/db/mw/msg.html?mid=2034299
>>>>
>>> Thanks!
>>>
>>> Now, how can I make it always case-insensitive?
>>>
>>
>> from http://www.sai.msu.su/~megera/postgres/gist/ltree/
>>
>> It is possible to use several modifiers at the end of a label:
>>
>>
>> @ Do case-insensitive label matching
>> * Do prefix matching for a label
>> % Don't account word separator '_' in label matching,
>> that is 'Russian%' would match 'Russian_nations',
>> but not 'Russian'
>>
>>
>>
>>>
>>>
>>>
>>
>> Regards,
>> Oleg
>> _____________________________________________________________
>> Oleg Bartunov, sci.researcher, hostmaster of AstroNet, Sternberg
>> Astronomical Institute, Moscow University (Russia) Internet:
>> oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
>> phone: +007(095)939-16-83, +007(095)939-23-83
>
> Does that apply to each node, or the entire string?
>
> I'd like to not have to parse the lquery string and make each node following
> it with an @.

I'm a little bit tired :), if you want case insenstive for the whole node,
you could use built-in fuinction 'lower(text)' !

use text2ltree(lower(text))

>
> LER
>
>
>

Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

In response to

Browse pgsql-general by date

  From Date Subject
Next Message Surabhi Ahuja 2005-02-08 17:44:57
Previous Message Larry Rosenman 2005-02-08 17:08:44 Re: Creating an index-type for LIKE '%value%'