On Wed, 9 Feb 2005 00:15:38 -0500, mhthomas <qnxodba_at_gmail.com> wrote:
> Hi John,
>
> I'll take a different approach than the other replies. You have some
> good replies so far.
>
> If you really care about performance of database links, its essential
> you learn how to trace the performance on both ends of each link.
> Then, if you see a problem (I've still got unexplained wonders that
> bother me at night... unresolved... you get the idea) you can trace
> and explain plan everything and track down any issues or bugs or
> settings.
I don't see that anyone has yet mentioned the DRIVING_SITE optimizer
hint. You may well need this, not least because (depending on version)
various relevant statistics (like nullability of columns or expected
cardinality IIRC) may not get pushed into the CBO on the instance in
which you issue your query from the remote site.
--
Niall Litchfield
Oracle DBA
http://www.niall.litchfield.dial.pipex.com
--
http://www.freelists.org/webpage/oracle-l
Received on Wed Feb 09 2005 - 03:36:27 CST
