Re: equivalence class not working?

Поиск
Список
Период
Сортировка
От Tom Lane
Тема Re: equivalence class not working?
Дата
Msg-id 18394.1137448003@sss.pgh.pa.us
обсуждение исходный текст
Ответ на equivalence class not working?  (uwcssa <uwcssa@gmail.com>)
Ответы Re: equivalence class not working?  (uwcssa <uwcssa@gmail.com>)
Список pgsql-hackers
uwcssa <uwcssa@gmail.com> writes:
> I am using postgres 8.1.  In indxpath.c, it says " Note: if Postgres tried
> to optimize queries by forming equivalence
> classes over equi-joined attributes (i.e., if it recognized that
> aqualification such as "where
> a.b=3Dc.d and a.b=3D5" could make use of
>  an index on c.d), then we could use that equivalence class info here with
> joininfo_list to do more complete tests for the usability
> of a partial index.  .....  XXX as of 7.1, equivalence class info *is*
> available."

Are you deliberately ignoring the rest of the comment?
        regards, tom lane


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: Anyone see a need for BTItem/HashItem?
Следующее
От: Martijn van Oosterhout
Дата:
Сообщение: Re: ScanKey representation for RowCompare index conditions