"Connor McDonald" <connor_mcdonald_at_yahoo.com> wrote in message
news:419C9CAB.1659_at_yahoo.com...
> Oradba Linux wrote:
> >
> > Connor McDonald wrote:
> > > Oradba Linux wrote:
> > >
> > >>I have gathered statistics for all objects in our prod database.
> > >>How do you guys find out the next time to gather stats on the table?
> > >>Do you regularly put them in a schedule ? My intention is avoid
wasting
> > >>cpu cycles gathering statistics unless it is needed.
> > >
> > >
> > > check out the MONITORING clause for tables
> > >
> > > hth
> > > connor
> > Hello Connor
> >
> > I have just ordered your book. I am liking the reviews a lot. Hopefully
> > i will not be disappointed.
> > The reason i dont want to turn on monitoring for all tables is the
> > overhead. Is this overhead too much? I am looking for opinions.
> > Also it is a datawarehouse/reporting db.
> > I am on oracle 9204 / sun os 32 bit
>
> There is an overhead but I'll doubt you'll notice it. Its predominantly
> memory based (and latch-less) with the data only being flushed down the
> the data dictionary at regular intervals.
>
> In fact, in v10, all tables are monitored as a default.
>
> hth
> connor
> --
> Connor McDonald
> Co-author: "Mastering Oracle PL/SQL - Practical Solutions"
> ISBN: 1590592174
>
> web: http://www.oracledba.co.uk
> web: http://www.oaktable.net
> email: connor_mcdonald_at_yahoo.com
>
> Coming Soon! "Oracle Insight - Tales of the OakTable"
>
> "GIVE a man a fish and he will eat for a day. But TEACH him how to fish,
> and...he will sit in a boat and drink beer all day"
>
> ------------------------------------------------------------
- Will i not notice this on a heavy OLTP DB? Is this so lightweight?
- My question is more what if 10% of the table which has say 60 mil rows
have changed, do i have to gather statistics again?
- If i go do an update without actually changing the data, it will still
show up in dba_tab_modifications view.
It will not happen in a live system guaranteed. does this mean that i
should gather stats again
- According to metalink support note <> it is says it is enough to
gather stats using 5% estimate. Has anybody seen this not to
work well.
I want to know how statistics gathering is handled in real live system
OLTP/DSS.
Thanks in advance
Received on Thu Nov 18 2004 - 12:02:29 CST
