Re: CBO stupid !!!

From: Keith Boulton <boulkenospam_at_globalnet.co.uk>
Date: Sat, 30 May 1998 10:58:25 GMT
Message-ID: <356fe5d7.11822161@read.news.global.net.uk>

On Sat, 30 May 1998 10:35:32 GMT, eis_at_mail.otenet.gr wrote:

>
> Hi,
>
> We use Oracle 7.2.2.4 on SCO UNIX 3.2.4.2. I must say we are very
> happy Oracle users. Initially we started with optimizer mode = RULE
> so we could migrate smoothly from Oracle 6.0.37. Then we switched
> on the COST mode. Though generaly CBO works ok, at times it
> makes stupid decisions!
>

Setting the initialisation parameter OPTIMIZER_MODE=FIRST_ROWS may help. By default, CBO tends to choose full table scans inappropriately. Received on Sat May 30 1998 - 05:58:25 CDT