Oracle-L: RE: DB Refreshes

From: <Jared.Still_at_radisys.com>
Date: Mon, 26 Aug 2002 15:48:18 -0800
Message-ID: <F001.004BFD95.20020826154818@fatcity.com>

Dennis,

I'd think that call would depend on the amount of activity that is taking place on the tables.

Replicating 2092 tables for read only access shouldn't be that difficult.

I wouldn't try it with OEM. Building a set of scripts to generate the replication
SQL is not too hard. As long as the refreshes don't impose too large a drain on network resources, I can't foresee any problems.

The biggest drain of course is building the initial snapshots. That may take some time.

Though that is a lot of tables, it may be that only a small percentage of them are regularly DML'd.

Have you tried snapshotting a large number of tables? I haven't, so maybe you've run into problems I have yet to see.

I've found snapshots to be very low maintenance, once implemented.

Jared

DENNIS WILLIAMS <DWILLIAMS_at_LIFETOUCH.COM> Sent by: root_at_fatcity.com
08/26/2002 03:13 PM
Please respond to ORACLE-L

        To:     Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
        cc: 
        Subject:        RE: DB Refreshes

Gulamabbas - If you're looking for minimal work, and must keep 2,092 tables
synchronized, I would take a hard look at the methods besides snapshots. Just my 2 cents worth.
Dennis Williams
DBA
Lifetouch, Inc.
dwilliams_at_lifetouch.com

-----Original Message-----
Sent: Monday, August 26, 2002 2:08 PM
To: Multiple recipients of list ORACLE-L

Thanks for the response Dennis, I got a very good idea from your email, here
is my situation our OLTP DB is 24/7 but the reporting DB has to be refreshed
on a nightly basis thus I can consider the snapshot. The only problem I see
with this, I will have to have a snapshot for over 2092 tables. Will have to
read more about snapshot documentation and how best to implement this. We are planning to use RMAN for backups/restores so maybe that could be another
option. We have 2 separate servers one for the OLTP and 2nd for the DSS sharing the SAN.

Any other suggestions/comments more than welcomed

Thanks

DENNIS WILLIAMS wrote:

Gulamabbas - I was in agreement with you until you said "minimal work". Funny. I am going to list some alternatives for you to consider, but the best alternative will depend on 1) how large is your OLTP database, 2) how active is the data i.e., how many transactions are involved, 3) can the reporting database be stand-alone, or does its data need to be integrated with other data?

Snapshots, replication. Good if the OLTP database isn't too active, but it can impose a load on the production system. If you can wait and resynchronize the databases at night when activity is lower, this will help. There are other alternatives along these lines, but these work best if there is minimal update activity.
RMAN DUPLICATE command can recover the database with minimal impact on the OLTP database.
Hot backup / clone. If you are using o.s. hot backups, t! ! hese can recreate a cloned database on the reporting system.
Transportable tablespaces.
Oracle standby database. Apply the archive logs from the OLTP database at night, switch it to being a reporting database during the day. With Oracle9i, you can do both simultaneously which means your reporting database can function as an current standby for production.

Dennis Williams
DBA
Lifetouch, Inc.
dwilliams_at_lifetouch.com

-----Original Message-----
Sent: Monday, August 26, 2002 11:28 AM
To: Multiple recipients of list ORACLE-L

Hello All

I am in need to know/leanr about the database refreshes. Here is my situation. We have OLTP database which is 24/7 and we need to provied to the
client a copy of the same OLTP database refreshed daily for their reporting
puposes. Any ideas/suggestions how best can I do this, with minimal work? I
am currently reading about ORACLE Snapshots. We are running ORACLE 8! ! .1.7.3.0
on Tur64 Unix.

Thanks

Gulamabbas Sikiladha
1315-2850 Cedarwood Dr
Ottawa, Ontario
Canada
K1V 8Y4
Tel : (613) 260 0336

Do You Yahoo!?
Yahoo!
Finance - Get real-time stock quotes

--

Please see the official ORACLE-L FAQ: http://www.orafaq.com
--

Author: DENNIS WILLIAMS
INET: DWILLIAMS_at_LIFETOUCH.COM Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists

To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP com! ! mand for other information (like subscribing).

Gulamabbas Sikiladha
1315-2850 Cedarwood Dr
Ottawa, Ontario
Canada
K1V 8Y4
Tel : (613) 260 0336

Do You Yahoo!?
Yahoo! <http://rd.yahoo.com/finance/mailsig/new/*http://finance.yahoo.com> Finance - Get real-time stock quotes

--

Please see the official ORACLE-L FAQ: http://www.orafaq.com
--

Author: DENNIS WILLIAMS
INET: DWILLIAMS_at_LIFETOUCH.COM

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------

--

Please see the official ORACLE-L FAQ: http://www.orafaq.com
--

Author:
INET: Jared.Still_at_radisys.com

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------