I'm sorry if this part of the answer should not be given in this context, but I happen to be in this list (as a lurker for most of the time) and be a Django user. Till Django 4.2 (LTS) postgres 12 is supported. Django 5.2 (LTS also) supports postgres 17+.
On Wed, 2025-06-11 at 16:39 +0545, Kushal Shri wrote: > We are in the process of planning a PostgreSQL upgrade and would greatly > appreciate any insights, best practices, or lessons learned from your experiences. > > Current Setup: > - PostgreSQL version: 9.5 > - Django version: 2.0 > - Database size: ~3 TB > - One Master 4 Replicas(Streaming Replication) > > We are taking a phased approach to this upgrade. In Phase 1, our goal is to > upgrade PostgreSQL from v9.5 to v12, ensuring compatibility with our current > Django 2.0 application.
That's already wrong. PostgreSQL v12 is out of support. Upgrade to v17 or v18.
> As part of this, I would like to understand: > > - What is the highest PostgreSQL version reliably supported with Django 2.0?
You'll have to ask Django what they support.
> - What upgrade strategies or methods have worked well for you in similar environments?
pg_upgrade --link
> - Any gotchas or performance considerations to keep in mind with large databases > during such upgrades?
Make sure you don't have millions of Large Objects, otherwise the upgrade will be very slow and memory consuming.
