Allthough there is a warning - when trying to use PostgreSQL 17 database with Nextcloud (…30), is somebody on his way migrating the previous pgsql 16.x main to 17 main?
What are the expectable problems ? Or if there are no serious probs - what can be done to suppress the warning in the admin settings?
PG-Tune also has upgraded their website to support PostgreSQL 17
→ PGTune - calculate configuration for PostgreSQL based on the maximum performance for a given hardware configuration
I can’t answer your actual questions, and I don’t think many here can, since version 17 has only been out for a few days.
However, I don’t think it’s worth taking any chances, unless you intend to test it and actively contribute to Nextcloud to get it officially supported, which has no urgency whatsoever, since every Postgresql version is supported for 5 years.
https://www.postgresql.org/support/versioning/
| Version | Current minor | Supported | First Release | Final Release |
|---|---|---|---|---|
| 17 | 17.0 | Yes | September 26, 2024 | November 8, 2029 |
| 16 | 16.4 | Yes | September 14, 2023 | November 9, 2028 |
| 15 | 15.8 | Yes | October 13, 2022 | November 11, 2027 |
| 14 | 14.13 | Yes | September 30, 2021 | November 12, 2026 |
| 13 | 13.16 | Yes | September 24, 2020 | November 13, 2025 |
| 12 | 12.20 | Yes | October 3, 2019 | November 14, 2024 |
For production instances, I would generally recommend sticking with the versions that Nextcloud officially supports, be it PHP or the database, and only upgrade to a new major version when it is officially supported by Nextcloud, unless you know exactly what you are doing and why you are doing it.
OK if it has no benefit or indends producing performance probs for NC migrating postgresql makes no sense and it’s fine to wait.
I just tested a migration to verify that it is possible. Never the less the warning in NC 30 using a db not inbetween >=12 and <=16 came a little bit surprisingly.
The last migration from 15 to 16 doesn’t give any warnings or restriction hints - maybe NC has been sufficient developed to support the 16 main version that moment postgresql has been released it’s new main version.
Thanks for reply.
Cheers 
I am not a database expert, but yes, newer versions can of course offer performance improvements. However, in many cases, applications will need to be adapted as well to take advantage of these performance improvements, especially if those improvements are associated with new database features.
It is therefore very likely that you will notice no difference at all or only minor performance improvements, but in the worst case, if there are significant changes in a new release, performance may even decrease, or if there are actual incompatibilities, it can also result in certain features of Nextcloud not working or even data loss, although the latter is rather unlikely.
So at the end of the day, you have to ask yourself if it’s worth the risk of being an early adopter. I would say no, unless there is a very specific reason to upgrade to the new version, but even then you should probably test it extensively before using it on a production system.
They may have added the check more recently. Also, this warning does not necessarily mean that there will be issues with the new version. I would interpret it more as ‘not supported’ or ‘not tested’, which in turn means ‘you’re on your own’ 
Mind to log an issue at Issues · nextcloud/server · GitHub that PostgreSQL 17 was released?
We will update our CI and adjust the check if applicable.
Until then, you have to live with the warning.
I’m actually running NC 30 and PG 17 and do not have any problems with that. At least i don’t know. I’m not power user. If someone knows some tasks to verify proper working, would be great to tell me.