RE: two instance -- one database
- From: "Mercadante, Thomas F (LABOR)" <Thomas.Mercadante@xxxxxxxxxxxxxxxxx>
- To: <Mark.Brady@xxxxxxxxxxxxxxxxx>, "oracle-l" <oracle-l@xxxxxxxxxxxxx>
- Date: Wed, 24 Sep 2008 13:01:24 -0400
Mark,
Have you tested a multi-table join across the database link?
Pick two very large tables.
Create a query and run it on the source database with timing turned on.
Run the same query on the remote database and compare the timings.
This used to be a very big issue. The "where" clause used to be
executed locally which means that all data from both tables was brought
across the database link and joined locally. A very bad arrangement.
I agree with Tim Gorman. It accomplishes nothing and adds complexity at
your personal cost. You will be tuning this arrangement forever.
Tom
________________________________
From: oracle-l-bounce@xxxxxxxxxxxxx
[mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Brady, Mark
Sent: Wednesday, September 24, 2008 11:07 AM
To: oracle-l
Subject: two instance -- one database
I have a friend (no really, this isn't some lame way of telling you
about me but trying to hide that by ... )
I have a friend, and at his company they have an Oracle database with
tables and data. We'll call it Database A and they have another Database
B that has views across dblinks to each of the tables in Database A. The
data team says that this protects Database A from bad queries.
So can anyone think of any possible benefit from this arrangement? Will
administration be easier, queries faster, performance more predictable?
Anything?
>>> This e-mail and any attachments are confidential, may contain legal,
professional or other privileged information, and are intended solely
for the addressee. If you are not the intended recipient, do not use
the information in this e-mail in any way, delete this e-mail and notify
the sender. CEG-IP1
Other related posts:
