Thinking of moving to PostgreSQL

Thinking of moving to PostgreSQL

They say timing is everything, and only last week I was talking to Brett Cameron about databases on OpenVMS; you know the dialogue: what is the future; is it proprietary or open, relational, or NoSQL, DBaaS, and so on? The usual stuff. Then this article dropped onto my desk, and I thought “that rings a bell”:

Databases with meatballs - IKEA's migration from flat(pack) data model to open source Postgres

This reminded us of why in 2018 we initially ported the PostgreSQL client API to VSI OpenVMS in the first place; this work was done at the request of a specific customer for exactly the reasons discussed in this article. This was a joint project between the customer, VSI, and our migration partner Sector7, with the end goal being to migrate the customer off their existing proprietary database and on to PostgreSQL on a Linux system, with connections to their OpenVMS application via the PostgreSQL client. Porting the PostgreSQL client was relatively straightforward; however from the customers' perspective this was a massive project, involving the migration of several hundred databases to PostgreSQL, and in fact the rollout has just recently completed.

While there is no doubt this project is a major effort, the key benefits to the customer are obvious, namely a very considerable saving on license fees (if you have several hundred databases then software license fees can soon add up), and access to a much larger (and not declining) pool of skilled resources. As an added bonus, the customer has noted that (after some tuning) most database queries in fact perform better in the new environment.

Now, while it is true that PostgreSQL might not suit every situation, for this project it was absolutely ideal, and I suspect it would be a good fit for many others in the OpenVMS Nation.

Looking forward, the story gets even better, as we will soon have at least 2 options to use PostgreSQL with OpenVMS:

  1. The first option is still based on the standard application server/database server model, except with the advent of OpenVMS 9.2 this model could take on a slightly different look. Imagine your application on OpenVMS in one VM and your database server in another VM on the same system (think containers as well).

  2. The second option might be even more attractive. SSIO (Shared Stream I/O) is mentioned on our roadmap, and once this is available, customers will be able to run PostgreSQL (and other applications requiring SSIO) natively on their OpenVMS systems, which is most definitely something to look forward to.

If you want to know more about PostgreSQL, take a look at the community website at, and you can read about the Sector7 PostgreSQL migration solution at

If you want to talk about database migrations then contact VSI at

Chris Brown

Sep 9th, 2021

Chris Brown

Director of Strategy for VMS Software, Inc.