Re: Does this matter?
От | Andrew Sullivan |
---|---|
Тема | Re: Does this matter? |
Дата | |
Msg-id | 20021101161057.V5799@mail.libertyrms.com обсуждение исходный текст |
Ответ на | Re: Does this matter? (Philip Hallstrom <philip@adhesivemedia.com>) |
Ответы |
Re: Does this matter?
|
Список | pgsql-performance |
On Fri, Nov 01, 2002 at 12:53:29PM -0800, Philip Hallstrom wrote: > > is padded out to the specified length. Therefore the index on a char(36) > > column will be a little larger, and thus a little slower, than the char(20). > > > > Really? According to this url (search for "Tip") there is no performance > difference just a space difference. I don't know for sure either way, but > if there is a difference the manual needs updating. Hmm. Maybe a clarification, but I don't think this is quite what the tip is talking about. The tip points out that part of the cost is "the increased storage" from the blank-padded type (char) as contrasted with non-padded types (like text). The tip isn't talking about whether a length of 20 is faster than a length of 36. Anyway, I can't really believe the length would be a big deal except on really huge tables. A -- ---- Andrew Sullivan 204-4141 Yonge Street Liberty RMS Toronto, Ontario Canada <andrew@libertyrms.info> M2P 2A8 +1 416 646 3304 x110
В списке pgsql-performance по дате отправления: