Re: [PATCHES] Avg performance for int8/numeric

Поиск
Список
Период
Сортировка
От Tom Lane
Тема Re: [PATCHES] Avg performance for int8/numeric
Дата
Msg-id 19371.1164561276@sss.pgh.pa.us
обсуждение исходный текст
Ответ на Re: [PATCHES] Avg performance for int8/numeric  ("Simon Riggs" <simon@2ndquadrant.com>)
Ответы Re: [PATCHES] Avg performance for int8/numeric  (Mark Kirkwood <markir@paradise.net.nz>)
Список pgsql-hackers
"Simon Riggs" <simon@2ndquadrant.com> writes:
> On Sat, 2006-11-25 at 18:57 +1300, Mark Kirkwood wrote:
>> Also Neil suggested investigating using a single composite type
>> {int8, 
>> numeric} for the {N,sum(X)} transition values. This could well be a 
>> faster way to do this (not sure how to make it work yet... but it
>> sounds 
>> promising...).

> If that is true it implies that any fixed length array is more expensive
> than using a composite type.

Not sure how you derived that conclusion from this statement, but it
doesn't appear to me to follow at all.  The reason for Neil's suggestion
was to avoid using numeric arithmetic to run a simple counter, and the
reason that this array stuff is expensive is that the array *components*
are variable-length, which is something that no amount of array
redesigning will eliminate.
        regards, tom lane


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Andrew Dunstan
Дата:
Сообщение: Re: [CORE] RC1 blocker issues
Следующее
От: "Jeroen T. Vermeulen"
Дата:
Сообщение: Re: "Optional ident" authentication