Re: [despammed] question about index

Поиск
Список
Период
Сортировка
От Andreas Kretschmer
Тема Re: [despammed] question about index
Дата
Msg-id 20041216110139.GA5899@Pinguin.wug-glas.de
обсуждение исходный текст
Ответ на question about index  (Jerome Alet <alet@librelogiciel.com>)
Ответы Re: [despammed] question about index
Список pgsql-sql
am  16.12.2004, um 11:41:54 +0100 mailte Jerome Alet folgendes:
> Hi,
> 
> For a future databas, I plan to have got a table with a text field 
> which can contain only three different values, say "VALUE1", 
> "VALUE2", and "VALUE3" 

Why text-fields for this task? I would prefer a smallint for this with a
check-contraint to check the values.

> be as fast as possible.        
> 
> considering that almost 70% of the rows will be with 'VALUE1', 20%
> will be with 'VALUE2' and 10% will be with 'VALUE3' on the average.
> 
> should I create an index to speedup the counts or not ?

Yes.



Andreas
-- 
Andreas Kretschmer    (Kontakt: siehe Header)              Tel. NL Heynitz:  035242/47212
GnuPG-ID 0x3FFF606C http://wwwkeys.de.pgp.net===    Schollglas Unternehmensgruppe    === 


В списке pgsql-sql по дате отправления:

Предыдущее
От: Jerome Alet
Дата:
Сообщение: question about index
Следующее
От: Janning Vygen
Дата:
Сообщение: Re: Query aid