Re: Simple Column reordering

Поиск
Список
Период
Сортировка
От Bruce Momjian
Тема Re: Simple Column reordering
Дата
Msg-id 200702232227.l1NMRF526448@momjian.us
обсуждение исходный текст
Ответ на Re: Simple Column reordering  (Lukas Kahwe Smith <smith@pooteeweet.org>)
Ответы Re: Simple Column reordering  (Lukas Kahwe Smith <smith@pooteeweet.org>)
Список pgsql-hackers
Lukas Kahwe Smith wrote:
> Simon Riggs wrote:
> 
> > If this is standards-breaking as you say, I would withdraw immediately.
> > I checked the SQL standard and could not see how this would do so. The
> > standard states SELECT * would return columns in order; it doesn't say
> > what that order should be, nor does CREATE TABLE enforce the ordering to
> > be the same as it has specified, AFAICS. Please correct me and I will
> > withdraw. Practical issues seem far stronger drivers than standards
> > issues here, which is why the parameter would default=off.
> 
> I did not follow the entire thread. I just wanted to point out that IIRC 
> MS SQL Server (and maybe also Sybase) do automatically optimize the 
> internal order of how columns are stored to move fixed length (which 
> also means non NULLable for these two servers) columns to the left. 
> Maybe this will serve as a reference point (not necessarily for 
> standards compliance of course).

And that optimized ordering shows up with SELECT *?

--  Bruce Momjian  <bruce@momjian.us>          http://momjian.us EnterpriseDB
http://www.enterprisedb.com
 + If your life is a hard drive, Christ can be your backup. +


В списке pgsql-hackers по дате отправления:

Предыдущее
От: "Merlin Moncure"
Дата:
Сообщение: urgent: upgraded to 8.2, getting kernel panics
Следующее
От: Ron Mayer
Дата:
Сообщение: Re: SCMS question