Re: Index Usage and Running Times by FullTextSearch with prefix matching

Поиск
Список
Период
Сортировка
От rawi
Тема Re: Index Usage and Running Times by FullTextSearch with prefix matching
Дата
Msg-id 1371807089696-5760297.post@n5.nabble.com
обсуждение исходный текст
Ответ на Re: Index Usage and Running Times by FullTextSearch with prefix matching  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-sql
Tom Lane-2 wrote
> rawi <

> only4com@

> > writes:
>> And querying: FTS with prefix matching:
> 
>> SELECT count(a)
>> FROM t1
>> WHERE a_tsvector @@ to_tsquery('aaa:* & b:* & c:* & d:*')
> 
>> (RESULT: count: 619)
>> Total query runtime: 21266 ms.
> 
> FWIW, I get fairly decent performance for cases like this in HEAD
> (at least with a GIN index; GIST seems much less able to do well with
> short prefixes).  What PG version are you testing?

Last tests with PG 9.2:

Whereas the "whole words" full text search stays at ~350ms for 900,000
records I tryed the number of records, which are becoming to make one
suffer, querying for prefixes:

RECORDS        RUNTIME (ms)
10,000        13
100,000        81
200,000        172
400,000        7,284
900,000        20,888

Regards, Rawi




--
View this message in context:
http://postgresql.1045698.n5.nabble.com/Index-Usage-and-Running-Times-by-FullTextSearch-with-prefix-matching-tp5759021p5760297.html
Sent from the PostgreSQL - sql mailing list archive at Nabble.com.



В списке pgsql-sql по дате отправления:

Предыдущее
От: David Johnston
Дата:
Сообщение: Re: UNNEST result order vs Array data
Следующее
От: Dev Kumkar
Дата:
Сообщение: Unquoted column names fold to lower case