Re: Analyze

From: Sybrand Bakker <gooiditweg_at_sybrandb.demon.nl>
Date: Tue, 08 Oct 2002 06:42:08 +0200
Message-ID: <1ao4qukvj5fbskrno59eipme2rcftutvcb@4ax.com>

On Mon, 07 Oct 2002 19:09:16 GMT, "Stephan" <test_at_test.com> wrote:

>Oracle 7.3.4 and higher:
>
>- Is ANALYZING tables a MUST to achieve good performance?
>(imagine you NEVER analyze tables)
>- After an import (of a specific user/schema), do I have to analyze the
>tables?
>- Is there 1 command to analyze ALL tables at once?
>
>Thanks
>Stephan
>

If you have *never* analyzed your tables you are probably still using the Rule Based Optimizer (which is going away, and exists for backwards compatability only), and analyzing your tables will switch to Cost Based Optimizer. Due to differences betweern the optimizers this is probably going to result in disaster
if you export with an appropiate statistics switch, import will do this for you
in 7.3.4 and 8.0 refer to the dbms_utility package, in 8i to dbms_stats

Hth

Sybrand Bakker, Senior Oracle DBA

To reply remove -verwijderdit from my e-mail address Received on Mon Oct 07 2002 - 23:42:08 CDT