Azure Managed Postgres hands out user names in the form of;

username@my-unique-instance-name

, so most often you actually need to URL encode the username to avoid having two

@

symbols in your connection string, e.g.

username%40my-unique-instance-name

. This is what I did and what the

db-upgrade

container was upset about. I hardcoded the full connection string in the helm template with the two

@

symbols and it worked straight away.