Have you read this section:
http://web2py.com/books/default/chapter/29/6#One-to-many-relation? (Think
person=group and dog=event.)
On Wednesday, June 27, 2012 12:42:40 PM UTC-4, Alec Taylor wrote:
>
> I was planning to have a many groups to 1 event relation, but now that
> I think of it, there are better ways of accomplishing that.
>
> How do I do the n+1 unrolling simply?
>
> I.e.: how do I create a list using SQLFORM (or similar) which finds
> and displays in a list all [events in [db.event for each group in
> db.group_of_events]]?`
>
> On Thu, Jun 28, 2012 at 2:34 AM, Anthony wrote:
> > Actually, why do you need the "events" field in group_of_events? If you
> want
> > a one-to-many relation with db.event, you've already got it with the
> > db.event.group_id field. What workflow are you trying to create?
> >
> > Anthony
> >
> >
> > On Wednesday, June 27, 2012 12:09:50 PM UTC-4, Alec Taylor wrote:
> >>
> >> Thanks, that fixed some other problems, but my initial problem of not
> >> getting the list of events associated with each group is still
> >> present.
> >>
> >> >> db.define_table(
> >> >> 'group_of_events',
> >> >> Field('group_name', requires=[IS_NOT_EMPTY(), IS_NOT_IN_DB(db,
> >> >> 'group_of_events.group_name')]),
> >> >> Field('events', 'list:reference db.event',
> requires=[IS_IN_DB(db,
> >> >> 'event.id', '%(event_name)s [%(group_id)s]', multiple=True)])
> >> >
> >> >
> >> > When you put the IS_IN_DB validator in a list, you do not get the
> >> > standard
> >> > dropdown (for single items) or multiple select widget (for multiple
> >> > items).
> >> > Change the above to:
> >> >
> >> > requires=IS_IN_DB(db, 'event.id', '%(event_name)s
> [%(group_id)s]',
> >> > multiple=True)
> >> > Anthony
> >> >
> >> > --
> >> >
> >> >
> >> >
> >
> > --
> >
> >
> >
>
