I have this nasty problem too, in early time, I don't know the problem, but we used it for a while,
than we found our table growing too fast without insert any record( we use update), this behaviour
most like M$ MSACCESS database I had used a long time ago which don't reuse deleted record
space and full fill your hard disk after several hours, the nasty vaccum block any other users to operate
on table, this is a big problem for a large table, because it will block tooo long to let other user to run
query. we have a project affected by this problem, and sadly we decide to use closure source database- SYBASE on linux,
wehavn't any other selections. :(
note that SYBASE and Informix both have 'update statistics' command, but they run it fast in seconds,
not block any other user, this is pretty. ya, what's good technology!
XuYifeng
----- Original Message -----
From: Martin A. Marques <martin@math.unl.edu.ar>
To: bpalmer <bpalmer@crimelabs.net>; <pgsql-hackers@postgresql.org>
Sent: Thursday, December 14, 2000 7:08 AM
Subject: Re: [HACKERS] Why vacuum?
El Mié 13 Dic 2000 16:41, bpalmer escribió:
> I noticed the other day that one of my pg databases was slow, so I ran
> vacuum on it, which brought a question to mind: why the need? I looked
> at my oracle server and we aren't doing anything of the sort (that I can
> find), so why does pg need it? Any info?
I know nothing about Oracle, but I can tell you that Informix has an update
statistics, which I don't know if it's similar to vacuum, but....
What vacuum does is clean the database from rows that were left during
updates and deletes, non the less, the tables get shrincked, so searches get
faster.
Saludos... :-)
--
System Administration: It's a dirty job,
but someone told I had to do it.
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Martín Marqués email: martin@math.unl.edu.ar
Santa Fe - Argentina http://math.unl.edu.ar/~martin/
Administrador de sistemas en math.unl.edu.ar
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