Re: Possible solution for LIKE optimization

Поиск
Список
Период
Сортировка
От Peter Eisentraut
Тема Re: Possible solution for LIKE optimization
Дата
Msg-id Pine.LNX.4.30.0108062140470.680-100000@peter.localdomain
обсуждение исходный текст
Ответ на Re: Possible solution for LIKE optimization  (Tom Lane <tgl@sss.pgh.pa.us>)
Ответы Re: Possible solution for LIKE optimization  (Tom Lane <tgl@sss.pgh.pa.us>)
Список pgsql-hackers
Tom Lane writes:

> On the other hand, LIKE *is* multibyte aware.  So the hypothetical
> non-locale-aware comparison operators would need to be aware of
> multibyte character sets even though not aware of locale.  And the
> "add one" operator that we postulated for the LIKE index optimization
> needs to be able to increment a multibyte character.

Both of these are not hard if you know how strcmp operates.  It would also
be irrelevant whether "add one" to a multibyte character yields another
valid multibyte character.  strcmp doesn't care.

-- 
Peter Eisentraut   peter_e@gmx.net   http://funkturm.homeip.net/~peter



В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: Possible solution for LIKE optimization
Следующее
От: Tom Lane
Дата:
Сообщение: Re: Re: AW: Re: OID wraparound: summary and proposal