Re: Memory usage / concept

hi,

i think it's your client (psql) what's actually crashing. it's attempting
to load all your rows into memory before displaying them. i'd recommend
using select * from foo order by something limit x offset y or using
cursor. i think there is no use for you to issue query like this...

see:
http://www.postgresql.org/idocs/index.php?queries-limit.html
http://www.postgresql.org/idocs/index.php?sql-declare.html
http://www.postgresql.org/idocs/index.php?sql-fetch.html

hope that helps, kuba

On Mon, 5 Aug 2002, Valerie Schneider DSI/DEV wrote:

> Hi, I'm a novice in PostgreSql. I'm used to work with Oracle. I'm testing
> PostgreSql (7.2) on linux RedHat 7.1 and Solaris 8. I have some problems
> with large queries : for example a "select * from my_table ..." and my_table
> with a size of several Gb and several Mrows. If I set the ulimit to
> "unlimited", I overflow my memory and my swap; if I limit it, my query
> crashes. In fact I don't know how PG works with the memory use :
> with Oracle I have to manage its memory space (the SGA); is there anything
> like that with PG ?
> Thanks, Valerie.
>
>
>
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