Re: Does pgsql's regex processor optimize Common-Prefix?

Kurapica,

I'd use contrib/pg_trgm for your application.

Олег
On Tue, 26 Dec 2006, Alvaro Herrera wrote:

> Kurapica wrote:
>
>> I am developing an application which searches for city names in a
>> column. There is a lot of cities and I have to 'like' every name which
>> is not effective enough. So I want to know whether pgsql's regex
>> processor can optimize regexes such as:
>>
>> Nebraska|Nevada|North Carolina
>> to
>> N(e(braska|vada)|orth Carolina)
>>
>> If the processor can do that like a Dictionary-Tree, it may be
>> affordable to me or else I have to write a matcher myself.
>>
>> Any suggestion is appreciated. Thank you and appologize for my poor English.
>
> Compared to the use of indexes to skip whole table scanning, this
> optimization is going to have very little impact.  So don't worry about
> it.
>
>

     Regards,
         Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
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