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Comment by ktosobcy | Hacker News Reader

Eh... interesting features, yet docker upgrade is still huge PITA because upgrade between major versions is not supported :/

I love PostgreSQL, but this is just utterly annoying and discouraging to use it…

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That is mostly an issue with the official docker image, not a PostgreSQL issue. Upgrading to a new major is easy if you use the Debian packages and is fine with a couple of minutes downtime. There is no reason a docker image could not do the same.

The issue with PostgreSQL which the Debian packages handle fine but the Docker Hub's image does not is that you need both the executables for the old and the new major version of PostgreSQL when upgrading. This just works with Debian packages but not with the Docker image.

I'm fully aware why it's an issue with official image. But even with debian (or any other "packaging") there are hoops to be hopped through due to said missing upgrade handling which IMHO is very annoying.

They do handle minor versions upgrade so the code handling upgrading is there but devs seems to be quite adamant against adding major version upgrade. I (well, a lot of people judging from votes and comments in https://github.com/docker-library/postgres/issues/37 and stars in https://github.com/tianon/docker-postgres-upgrade) would love that, and only between subsequent version would be more than enough…

> They do handle minor versions upgrade so the code handling upgrading is there but devs seems to be quite adamant against adding major version upgrade

Minor versions of PostgreSQL have constraints that major versions don't have; in that minor versions in principle don't see new features added. This allows minor versions of the same major release to run against the same data directory without modifications.

However.

Major versions add those new features, at the cost of changes to internals that show up in things like catalog layout. This causes changes in how on-disk data is interpreted, and thus this is incompatible, and unlike minor releases this requires specialized upgrade handling.

Well, yeah. But virtually all other software can peroform the data upgrad with single/new binary and only PostgreSQL requires old binaries to be available to run `pg_upgrade`...

I suggest you look into what pg_upgrade actually does because the "code handling upgrading" does not exist other than as pg_upgrade. And writing it would be a ton of work and would likely halt a lot of innovation in PostgreSQL and make it no longer a competitive database unless someone does a major re-architecting of PostgreSQL which likely would break all extensions.

The issue causing it is how PostgreSQL has implemented the system catalog.

> That is mostly an issue with the official docker image, not a PostgreSQL issue.

I wish Docker would stop calling their unofficial Postgres images “official”. :-/ (They're “official Docker”, but not “official Postgres”. The naming is deeply misleading for everyone who is not a Docker expert.)

this is not postgres' fault.

once the latest pgautoupgrade is available, you can do it with this:

    docker run --rm \
      -v YOUR_DATA_VOLUME:/var/lib/postgresql/data \
      -e POSTGRES_USER=USER \
      -e POSTGRES_PASSWORD=PW \
      -e POSTGRES_DB=DB \
      -e PGAUTO_ONESHOT=yes \
      pgautoupgrade/pgautoupgrade:18-bookworm

I recommend copying the volume first, in case any mistakes occur you can rollback.

I'm super curious about what special features / extensions you're using. The only painful upgrade for me from PostgreSQL 7 to 9 (2010 IIRC, building from scratch with SSL library issues). My next upgrade (exact same database, evolved a lot in complexity with stored queries, views, ~500x size) was from 9 to 11 (2022), and it was totally painless. A few weeks ago I migrated it from 11 to 17, zero issues.

Edit: Oh, for reference, I'm not using docker, just an AWS EC2 Amazon Linux instance, with a mirror on an Alpine Linux server. PostgreSQL installed via package repo, very little custom configuration.

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