risks of using cost based optimizer
From: Vincent BAUZAC <vbauzac_at_capgemini.fr>
Date: 6 Nov 2002 08:30:17 -0800
Message-ID: <85372317.0211060830.13d446ef_at_posting.google.com>
Date: 6 Nov 2002 08:30:17 -0800
Message-ID: <85372317.0211060830.13d446ef_at_posting.google.com>
Hi,
We have a production database (Oracle 8i) still using the 'RULE'
optimizer mode.
The Oracle documentation advises to use the statistics, but we have
heard there is some risks in doing this; the performance of some
request could be badly affected.
Is it true ?? What kind of request could be badly affected ??
Thanks for your help,
Since we have some performance troubles, we would like to switch it
into the 'CHOOSE' optimizer mode and compute the statistics, every
weeks for example.
Vincent Received on Wed Nov 06 2002 - 17:30:17 CET