Re: Data Migration options - oracle to oracle

From: Norman Dunbar <>
Date: Fri, 06 Sep 2013 11:38:00 +0100
Message-ID: <>

Hi Karth,

On 06/09/13 05:13, Karth Panchan wrote:

> Here is little more background information.
> ...

Another project I was involved in required that the source database be left untouched, but the target needed to be up to date. There was an air gap between, so shipping archived logs etc was out of the question.

After looking at the data, we discovered that a sequence was used as a surrogate PK in most of the tables, so we took an exp of the database at a particular sequence value - noted for all tables involved - and built the new database with that exp dump file.

When it came the go live weekend, we did a pile of exp with a query limiting the data to only that after the previously noted sequence values for the PKs, copied those over - by courier - to the new data centre and imported (appended) the data to the existing database. Worked a treat!

> We plan to migrate 100 customers per month, but we get only 24hours
> to migrate those 100 customers.

What happens afterwards? Do those customers no longer have access to the source database?

Partitioning is, I seem to remember, an added cost license! Like anything remotely useful! :-(

However, I'm not aware of any "maintenance nightmares" of exchange partition. Granted I don;t think it's as simple as the manuals would have you believe - especially if you have foreign keys etc. I might be wrong, I've only ever "played" with it myself as a potential problem solver for an application I worked with way back. (Oracle 8i) - management decided not to go ahead with it.

Problem is, if yo are partitioning the table, it's going to affect the current users plus you'll probably need to partition your indexes to suit and that will entail a recreate as opposed to a rebuild - that might affect current users.

Sorry I'm probably not helping!


Norman Dunbar
Dunbar IT Consultants Ltd

Registered address:
27a Lidget Hill
West Yorkshire
United Kingdom
LS28 7LG

Company Number: 05132767
Received on Fri Sep 06 2013 - 12:38:00 CEST

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