Script to update an older Postgres version's data to a newer Postgres version.

Also, for example, you might get an error like this when starting your Postgres container:

"The data directory was initialized by PostgreSQL version 16, which is not compatible with this version 17"

This will automate the data upgrade for you. Note that this script is specifically created for Postgres containers, since that is what I use, but I would imagine with minor tweaks it could easily be made to work for native installations as well.

• Creates a temporary Postgres "old" version container (the version with your current data to upgrade).
• Backs up your database(s) on the "old" version server to a .sql file.
• Compares the backed up .sql size to a minimum size you've set in the script config.
• Backs up your Data directory into a .tar archive.
• Compares the Data directory with that archive to be sure they're identical.
• Copies the backed-up .sql file into the archive, so you have all backups in 1 place.
• Optionally compresses the archive with Gzip or Bzip2
• Moves the archive to your chosen final resting place for it.
• Prepares the Data directory for the upgrade; validates User, permissions, etc.
• Creates a temporary Postgres "new" version container (the version upgrading to).
• Imports/Restores the backed-up .sql into the new Postgres version.

Then cleans up after itself.

After that, all you need to do is start the new version as you normally would, and it's all upgraded.

I've been using postgres:latest since around version 13 and it seems that Postgres updates major versions surprisingly often, killing all other containers that use a PGS database until I do all these steps manually, and personally, I've found having to stop everything I'm doing, look up all these steps to remember the procedure, then do them by hand to be a bit of a PITA.

So I took some time out to write this now, to save me even more time in the future. Thus it was born.

So far this same procedure has worked for me through versions 13-17 without issue.

1. Clone this repo (or just grab the script itself)

2. Edit the options to match your setup (most of the defaults should be fine)

3. Run it. (It must be run as root/sudo; it'll scold you if you try not to.)

   sudo ./JSE-Postgres-Update.sh

Bout it!

After it's done, you'll have a full backup of your SQL and Data, and the newer version of Postgres will have all of your data migrated. Just fire the new version up as you always do, using the new version tag.

This is it's "hello world" release, so I'm sure I might've missed some edge cases, and such. If so let me know in the issues.