risks of using cost based optimizer

Hi,

We have a production database (Oracle 8i) still using the 'RULE' optimizer mode.
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.

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,

Vincent Received on Wed Nov 06 2002 - 17:30:17 CET