Does COPY FROM gaurentee no partial rows?

A quick question, since this is not very obvious from the postgres or asyncpg docs: under what circumstances, if any, does copy_from_query guarantee that no partial rows will be delivered to the output coroutine?

In my experience this hasn't happened, and I could try some more exhaustive testing, but I imagine/hope that someone might just already know the answer.

To me the options seem to be:

• If the networking code reads one line at a time, then the 'text' format guarantees full rows, but not necessarily 'csv' or 'binary'
• Asyncpg itself or postgres itself may explicitly implement such a guarantee?
• Otherwise, there is no guarantee.

Beginne mit der PostgreSQL- und asyncpg-Dokumentation zu copy_from_query und verfolge anschließend, wie deren Ausgabekoroutine in den verfügbaren asyncpg-Materialien beschrieben wird. Dokumentiere die Umstände, sofern vorhanden, unter denen Text-, CSV- und Binärausgabe unvollständige Zeilen vermeiden, und stelle die Garantie für Benutzer klar dar.