One-line installers are fine. Automatic upgrades are not.

To use the GP's example of Postgres: I care a whole lot more about my data than anyone at Canonical does. It would be a firing offense to trust that Canonical handles a database software and data upgrade correctly.

Which is why Debian doesn't do upgrades-for-the-sake-of-upgrades in Stable. Anything you get there is a security fix, and the notes will tell you if there's an unavoidable functionality or config change.

It's also why you can easily set up your own repo in two stages: one that updates from upstream automatically, so you can test changes, and one that never updates except when you specifically update a package: that's the one that your production runs on.

Sure; which is why you have an update process - the includes checking for potential issues, and involves several avenues of upgrade (apt, direct, etc.).

With proper due diligence on our part I trust the package maintainers to make less mistakes than if I have to do it all by hand :)

apt is pretty configurable though. For example I get an automatic email every day notifying me of package upgrades that are available. Only security patches are installed automatically (you can even specify individual packages to be excluded altogether).

I've mainly used mysql and never lost data due to an upgrade (we backup before an upgrade anyway), YMMV of course.

> One-line installers are fine. Automatic upgrades are not

Are you talking about minor-version upgrades, security patches, etc? Or any kind of upgrade? I think there's a big difference.

In the case of minor-version upgrades or security patches, what exactly is apt-get taking away from you?