Обсуждение: Convert / Migrate From Oracle 11gR2 To PostgreSQL ? On CentOS 5.7 x86_64

On 7 Prosinec 2011, 15:13, Gene Poole wrote:
> This has to do with my personal home environment.
>
> I'm running Oracle 11gR2 DBMS with 4 instances using a single home
> directory.  For each of the instances I'm using LVM file systems with 10
> logical volumes defined (/dbmsu00 used for the install and /dbmsu01 - u09
> for the required files created using the DBCA utility). A single LISTENER
> created using the NETCA utility.

Not sure why you're doing this, but you can do something similar with
PostgreSQL. Running four clusters using the same set of binaries is not a
big deal.

> I chose Oracle because back in the dark ages I was a Oracle DBA when
> Oracle 7.3 was current. I've been told that it's OK to download and use
> the Oracle DBMS in a noncommercial environment for a limited time - well
> it's reached the end of that time.  I can't use the free Oracle XE because
> the database size limitations (4 GB).

Although this is a PostgreSQL list, I'll point out the limit is 11GB with
the current Oracle XE version (11g).

> Based upon what I've read and seen, the best choice for me is PostgreSQL
> Community Edition. What I need is advice, documentation, and information
> on how to take the above and move it from Oracle to PostgreSQL along with
> updating my JBoss 6.0 environment so it has access to the PostgreSQL
> databases/instances?  Can someone supply me with some direction?

PostgreSQL Community Edition? What is that? Do you mean sources that are
available for download from postgresql.org?

Switching the database in the AS is not a big deal - there's usually a
connection pool, so you need to add PostgreSQL JDBC driver and change the
config.

Porting the application is usually much harder, especially if you use
features that are available on Oracle only (or if you're hurt by some
Oracle-ism). If you're using native SQL, PL/SQL, etc. you'll have to
rewrite that. The complexity really depends on how your application is
coded, it's impossible to judge this.

Anyway, the simplest thing you can do is to give it a try. Install
PostgreSQL on a development environment and try to run the application.
It'll probably fail for some reason - fix the issue and repeat.

There are tools to make the switch easier - e.g. orafce package that
provides some compatibility features.

Tomas

On Wed, 07 Dec 2011 09:13:10 -0500, Gene Poole wrote:

> This has to do with my personal home environment.
>
> I'm running Oracle 11gR2 DBMS with 4 instances using a single home
> directory.  For each of the instances I'm using LVM file systems with 10
> logical volumes defined (/dbmsu00 used for the install and /dbmsu01 -
> u09 for the required files created using the DBCA utility). A single
> LISTENER created using the NETCA utility.
>
> I chose Oracle because back in the dark ages I was a Oracle DBA when
> Oracle 7.3 was current. I've been told that it's OK to download and use
> the Oracle DBMS in a noncommercial environment for a limited time - well
> it's reached the end of that time.  I can't use the free Oracle XE
> because the database size limitations (4 GB).
>
> Based upon what I've read and seen, the best choice for me is PostgreSQL
> Community Edition. What I need is advice, documentation, and information
> on how to take the above and move it from Oracle to PostgreSQL along
> with updating my JBoss 6.0 environment so it has access to the
> PostgreSQL databases/instances?  Can someone supply me with some
> direction?

I use PostgreSQL at home from *choice* (I am an Oracle DBA at work). But
I don't think there is any time limit on personal non-commercial use of
Oracle EE (you may want to check the OTN Licence Agreement on their
download page).

PostgreSQL is FOSS, so there are no "Editions", by the way.

Lastly, a couple of polite requests: Please do not post HTML, and please
consider carefully before crossposting to multiple groups.