Re: Update Statistics

Brent,

Thanks for the help and explanation.

Cheers,
Rob Panosh

"Brent" <bpathakis_at_yahoo.com> wrote in message news:1736c3ae.0210161902.43729b24_at_posting.google.com...
> "Rob Panosh" <rob_panosh_at_asdsoftware.com> wrote in message
 news:<3dade05c$1_at_news.splitrock.net>...
> > Anybody,
> >
> > I have an applications that runs against an Oracle 8i database ( 8.1.7 )
 and
> > all of a sudden I noticed that my select statements came to a crawl.
 Once I
> > ran compute statistics my SQL Select Statement performance went back to
> > normal. Can anybody give me a explanation about statistics? Is this
> > something I have to run every so often.
> >
> > Thanks,
> > Rob Panosh
>
>
> Hi Rob,
>
> You need to analyze the tables and indexes after a significant
> portion of the data has changed ( typically 10%) from inserts, updates
> or deletes. Oracle relies on the statistics to determine how to run
> your statement.
>
> One thing you might consider, depending on the size and activity
> of the table is to set it to monitoring:
>
> alter table my_table monitoring;
>
> And schedule a job to periodically run a command like:
>
> dbms_stats.gather_schema_stats('my_schema', cascade=> true,
> options => 'gather stale');
>
> The first will monitoring update, insert and delete activity on a
> table.
>
> The second will analyze schema, gathering statistics only tables
> that have changed 10% or more. The 'cacade => true' portion will
> analyze the indexes for the table.
Received on Thu Oct 17 2002 - 14:04:07 CEST