Results from Model.connection.execute

I am having trouble finding documentations on what this methods
returns.

I know for a SELECT query it will return an iterable object (although
I can't find any documentation on that).

I am doing a DELETE query.  When executed this should return the
number of affected rows, which is the best way to tell if the query
worked.  I'm also doing a COPY query.

Is there any way to get this result?

I am using postgres, so the result is a PGresult object, but that
object does not respond well to .inspect and has no docs.

Thanks.