query plan, outln, statistics, off topic

Hi,
1) For plan stability : Meaning I do not want too many surprises with query plan explain plan : for that one solution is use outline. However I think that might add overhead. Does anyone have any other input issues with outline.
2) I am thinking of having outline only for some users to limit the overhead. With a logon trigger. In the trigger the outline will be enabled. That way other users will be normal and this user will be outline. Any experience or issues with it. 3) How about if statistics are not gathered for existing tables and only gathered for new tables and in case of column additions. I understand some queries might get slow and not benefit from having recent statistics. Other than that any issue? Main aim here is to have a stable query plan meaning just have the same plan at least. Any issue with it? Will it be good with Oracle version upgrades? I did read that with new version old statistics are not good. However, we have some databases that did not get new statistics with upgrade and they seemed fine for the most queries part. In another 8i to 9i upgrade : Some queries were fine after the upgrade and till the statistics were generated some hours after upgrade. After statistics were generated they went bad. Any similar experiences or was I doing something wrong. I used the same script for generate. 4) Off topic : This is a good resource to get Oracle help. Does anyone know of similar google group or any other place to get help about general windows issues. For example any way to install software with non priv non admin account or work around. I see that there are groups like : comp.admin.policy ,comp.misc , comp.windows.misc but looks like they are not very frequently accessed. Thanks Received on Sun Apr 15 2007 - 15:19:07 CDT