44 messages in org.postgresql.pgsql-hackersRe: New feature request: FlashBack Query| From | Sent On | Attachments |
|---|---|---|
| RPK | Feb 17, 2007 6:49 am | |
| Joshua D. Drake | Feb 17, 2007 7:50 am | |
| Tom Lane | Feb 17, 2007 8:48 am | |
| elein | Feb 17, 2007 4:06 pm | |
| Chad Wagner | Feb 17, 2007 4:43 pm | |
| Joshua D. Drake | Feb 17, 2007 7:21 pm | |
| Chad Wagner | Feb 17, 2007 7:49 pm | |
| Tom Lane | Feb 17, 2007 9:31 pm | |
| Warren Turkal | Feb 17, 2007 10:46 pm | |
| Hannu Krosing | Feb 18, 2007 1:45 pm | |
| Joshua D. Drake | Feb 18, 2007 2:27 pm | |
| Andreas 'ads' Scherbaum | Feb 19, 2007 1:53 am | |
| Hannu Krosing | Feb 19, 2007 4:36 am | |
| Florian G. Pflug | Feb 19, 2007 6:13 am | |
| Alvaro Herrera | Feb 19, 2007 6:27 am | |
| Zeugswetter Andreas ADI SD | Feb 19, 2007 6:32 am | |
| Zeugswetter Andreas ADI SD | Feb 19, 2007 6:38 am | |
| Florian G. Pflug | Feb 19, 2007 6:59 am | |
| Gregory Stark | Feb 19, 2007 7:18 am | |
| tom...@tuxteam.de | Feb 19, 2007 8:18 am | |
| August Zajonc | Feb 19, 2007 10:09 am | |
| Florian G. Pflug | Feb 19, 2007 11:30 am | |
| August Zajonc | Feb 19, 2007 12:00 pm | |
| Tom Lane | Feb 19, 2007 7:39 pm | |
| Jonah H. Harris | Feb 19, 2007 8:53 pm | |
| Gregory Stark | Feb 20, 2007 12:58 am | |
| RPK | Feb 20, 2007 3:25 am | |
| Andrew Dunstan | Feb 20, 2007 4:42 am | |
| Jonah H. Harris | Feb 20, 2007 7:19 am | |
| Rod Taylor | Feb 20, 2007 7:42 am | |
| Hannu Krosing | Feb 20, 2007 8:02 am | |
| Gregory Stark | Feb 20, 2007 8:28 am | |
| August Zajonc | Feb 20, 2007 8:39 am | |
| RPK | Feb 20, 2007 10:27 am | |
| Tom Lane | Feb 20, 2007 10:40 am | |
| Theo Schlossnagle | Feb 20, 2007 10:45 am | |
| Jonah H. Harris | Feb 20, 2007 11:48 am | |
| Jonah H. Harris | Feb 20, 2007 12:03 pm | |
| August Zajonc | Feb 20, 2007 7:30 pm | |
| Csaba Nagy | Feb 21, 2007 1:17 am | |
| Florian G. Pflug | Feb 21, 2007 6:01 am | |
| Alvaro Herrera | Feb 21, 2007 6:13 am | |
| Florian G. Pflug | Feb 21, 2007 7:08 am | |
| August Zajonc | Mar 1, 2007 9:48 am |
| Subject: | Re: New feature request: FlashBack Query | |
|---|---|---|
| From: | Gregory Stark (sta...@enterprisedb.com) | |
| Date: | Feb 20, 2007 12:58:12 am | |
| List: | org.postgresql.pgsql-hackers | |
"Jonah H. Harris" <jona...@gmail.com> writes:
On 2/17/07, Joshua D. Drake <jd...@commandprompt.com> wrote:
My understanding is that the main difference is that rollbacks are inexpensive for us, but expensive for Oracle.
Yes, Oracle is optimized for COMMIT, we're optimized for ROLLBACK :)
I used to say that too but I've since realized it's not really true. It's more like Oracle is optimized for data that's committed long in the past and we're optimized for data that's been recently updated.
In Oracle the data that's been committed long in the past requires no transactional overhead but the data that's been recently updated requires lots of work to fetch the right version.
In Postgres it's the other way around. data that's been committed deleted long ago requires extra work to clean up but data that's been recently changed requires little additional work to see the correct version.
In a sense then it's the opposite of what we usually say. Oracle is optimized for mostly static data. Postgres is optimized for changing data.
-- Gregory Stark EnterpriseDB http://www.enterprisedb.com