On Oct 14, 2011, at 10:38 AM, Lloyd Kvam wrote: > Would it make sense to add a __nonzero__ method to ResultProxy that > was tied to the rowcount? > > def __nonzero__(self): > return bool(self.rowcount) > > This would allow code like > > if results: > process(results) > > I was surprised when this did not work.
this is because .rowcount is not related to the count of rows in a result set. Some DBAPI's may do this, but this is not the intent of .rowcount and is not supported on most. .rowcount is only intended to describe the number of rows matched by an UPDATE or DELETE statement. The only way to know if there are any rows in a result set are to fetch them. The cursor itself, based on backend, doesn't even know there's a row until it sends a message to the database to get the first row. Therefore you have to use fetchone() to check for a row. -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com. To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en.
