[Info-vax] Migrating from Rdb to Open Source Postgres

[Arne Vajhøj]

On 2/24/2023 2:44 PM, Denys Beauchemin wrote:
> Over the last several years, Postgres has acquired a solid reputation
> as a dependable, mission-critical RDBMS.  One of its benefit is that
> it’s Open Source, ie, license free.  You can install it on as many
> servers as you want, with any number of CPUs, for any number of
> users, no charge.

The cost is right.

:-)

And PostgreSQL has excellent support from cloud vendors as
managed service, which matters today.

> The Postgres server runs on Linux, and the application access the
> Postgres database over the network.  We used this technology to
> migrate IKEA’s store application that runs on OpenVMS on a server at
> every store around the world, to access a new Postgres server in
> every store. The application remained on OpenVMS and the Rdb service
> could be stopped, returning a bunch of cycles back to the
> application.

If PostgreSQL has been available (production ready) for VMS,
then the database could have stayed on VMS.

> This was all using Open Source Postgres and the Open Source client,
> supported by VSI, on OpenVMS.  The application got a performance
> improvement, and in certain cases, a sizable improvement and best of
> all, now that the application data is in Postgres, it can be accessed
> by a multitude of tools and apps on various platforms.  The
> application running on OpenVMS is no longer an island in the
> enterprise.

Rdb on VMS is very much accessible from tools and apps
on various platforms.

Oracle provide:
* ODBC driver
* JDBC driver
* ADO.NET provider
* SQL Services C API

That covers most use cases.

Arne