Update Statistics - Resolution setting

Hi. Solaris 10. IDS 10.00.FC6 Would there be any reason not to lower the default resolution setting of update stats high from 0.5% to 0.4%? I realize system catalog tables will grow and update stats will take a bit longer to run but those should only affect the actual run of the command not the after results. I want to lower the resolution as my data skew bar is a bit too high with the current default settings and there are values that are not being included as a skew and affecting the optimizer decisions negatively. Thanks, Zev Berezin

No reason not to improve the HIGH resolution at all. The lower the resolution the more buckets and so the more accurate the estimates that the optimizer makes. All to the good. The only time more is not better for data distributions is if the distribution is so volatile that it gives poor estimates. An example is a time column used for record filtering. Any rows inserted after the distributions are calculated are not included so the optimizer will assume that there are no rows with any values after the time the stats were last run and may choose the wrong index. Otherwise, more is better. Art On Tue, Feb 10, 2009 at 5:27 PM, Zev Berezin <zevb@bhphoto.com> wrote: > Hi. > > Solaris 10. IDS 10.00.FC6 > > Would there be any reason not to lower the default resolution setting of > update stats high from 0.5% to 0.4%? > I realize system catalog tables will grow and update stats will take a bit > longer to run but those should only affect the actual run of the command > not > the after results. I want to lower the resolution as my data skew bar is a > bit > too high with the current default settings and there are values that are > not > being included as a skew and affecting the optimizer decisions negatively. > > Thanks, > Zev Berezin > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > -- Art S. Kagel Oninit (www.oninit.com) IIUG Board of Directors (art@iiug.org) Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Oninit, the IIUG, nor any other organization with which I am associated either explicitly or implicitly. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. --0016e642d3a4fd165c0462989bc3