On Tue, 5 Nov 2019, Kevin Brannen wrote:
> The manual or others here are more knowledgeable than I, but I believe that
> for a "minor" upgrade, you can just swap out the code and restart PG. For
> major upgrades, the PG server is going to have to come down as the underlying
> files might be changed/transformed during the upgrade, ...
Files might change even with a minor upgrade. The few seconds it takes to
stop, upgrade, and restart the system prevents all errors due to
someone/something accessing the database while it's being upgraded.
Rich