Re: Online Oracle to Postgresql data migration

>
>
> > > >> We have an Oracle production database with some terbytes of data.
> > > >> We wanted
> > > >> to migrate that to Postgresql (rigt now...a test database and not
> > > >> production) database.
> > > >> What are the good options to do that?
> > > >> Please advise me on where to look for more information on this
> topic
> > > >
> > > > You have two steps to work on. The first is the DDL, to create
> > > > equivalent tables in pgsql as in oracle, the second is to migrate
> over
> > > > your data.
> > > >
> > I had done this with the test database. For ddl generation I used
> xml/xsl
> > and for data migration I used jdbc. I can get the ddl generated fine.
> With
> > JDBC the data migration is a bit slow.
> > My question is abt the data migration. Im not sure how to try this with
> an
> > online oracle database. We are required to run both postgres and oracle
> > database simultaneously for a couple of months (atleast till we decide
> > whether we are going to shut down oracle for good !!!). Since the oracle
> > database is a production database, It will have updates/inserts during
> this
> > time. How do you manage that?
> >
>
> About a year ago we converted one of our clients multi-TB ODS systems
> built in
> Oracle over to PostgreSQL. There's a case study about it you can get from
> the
> Sun folks at
>
> http://www.sun.com/third-party/srsc/resources/postgresql/postgre_success_dwp.pdf
>
> Now, due to the size of the project, we had to run both the Oracle and
> Postgres systems in parallel for several months. We kept the data up to
> date
> using a slew of custom code, designed to replicate data from either the
> ODS
> system or the OLTP system, depending on various technical and business
> factors. My guess is that in your case, you'd want a mix of replicating
> data
> from the current Oracle database and your application, as best possible.
>
> Figuring out how you go about replicating the data is certainly easier if
> you've have been through it before, but I don't think it is anything too
> magical; we went through a number of different ideas and ended up using
> multiple methods depending on the data involved. HTH.
>
Thanks .
We have around 3TB of data now running in Oracle. I have done replication in
postgresql but not much in Oracle. Is there a way you can replicate between
Oracle and Postgresql. For writing the custom codes do you suggest any
preferred language ...like java, perl etc?

Thanks
Josh