It's very easy to cause in the ORM because by default a chain of SELECTs may ready different committed data unless you add row level locks like FOR SHARE . In a horizontally scaled backend you need these locks usually, but it takes scanning the DB log to figure out how to get them in the right place.

You can't effectively use an ORM without detailed knowledge of the generated output unfortunately. It does not add locks for you, so it's probably just wrong in prod when horizontally scaled and requests span multiple statements.