Re: IS NOT DISTINCT FROM + Indexing

Поиск
Список
Период
Сортировка
От Peter Geoghegan
Тема Re: IS NOT DISTINCT FROM + Indexing
Дата
Msg-id CAM3SWZQrrdTZ-BR9L+rS5ZAxz7_x0Ysijwvc+vj46bLrtK1f+Q@mail.gmail.com
обсуждение исходный текст
Ответ на Re: IS NOT DISTINCT FROM + Indexing  (Andres Freund <andres@anarazel.de>)
Список pgsql-hackers
On Mon, Jul 21, 2014 at 4:57 PM, Andres Freund <andres@anarazel.de> wrote:
> I rather doubt it will. x in (y1, ... yn) is essentially expanded to x =
> y1 OR x = y2, ... OR x = yn. I.e. the NULL comparison will be done using
> normal equality comparison and thus not return a row with a NULL
> orderid. Am I missing something?

I was a little bit incautious in my use of words. The point is that a
scanKey could easily represent a ScalarArrayOpExpr with NULLs and
non-NULLs.
-- 
Peter Geoghegan



В списке pgsql-hackers по дате отправления:

Предыдущее
От: Andres Freund
Дата:
Сообщение: Re: IS NOT DISTINCT FROM + Indexing
Следующее
От: "MauMau"
Дата:
Сообщение: Re: [bug fix] Suppress "autovacuum: found orphan temp table" message