[GENERAL] Clients disconnect but query still runs

[Robert James]

Hi.  I noticed that when clients (both psql and pgAdmin) disconnect or
cancel, queries are often still running on the server.  A few questions:
1) Is there a way to reconnect and get the results?
2) Is there a way to tell postgres to automatically stop all queries when
the client who queried them disconnects?
3) Is there a way to see all queries whose clients have disconnected?
4) And finally: Why is this the behavior? Doesn't this keep some very long
queries running which drain performance but don't seem to benefit anyone?