[Zope] [ADVANCED] How do YOU guys do many-to-many in Zope without relational?

[Trevor Toenjes]

Oh yeah!
Zclasses instances dont include "title"s.
You have to instantiate themselves in the "property sheet" or elsewhere.

> -----Original Message-----
> From: zope-admin@zope.org [mailto:zope-admin@zope.org]On Behalf Of
> Trevor Toenjes
> Sent: Monday, October 22, 2001 3:58 PM
> To: Max M; Zope@Zope. Org
> Subject: RE: [Zope] [ADVANCED] How do YOU guys do many-to-many in Zope
> without relational?
>
>
> I just completed a similar project linking 2 Zclasses to cross-reference
> each other.
> I would like to see another reply to your Q to soft-link zclass instances
> rather than using a programmatic list.
>
> > But if someone renames, deletes or moves a subject I am f.*?d Or
> > the student
> > is. The relation to the subject is invalidated.
>
> Allow someone to rename the "title" property, but not change the ID of the
> Zclass instance (lock the ID once it is created, so users cant rename it).
> This will retain link integrity.
>
> If they delete the instance, then there is no relationship to maintain
> anyway, so who cares, or create a Subject "status" property to throw up an
> exception to notate that the Subject is in "delete" status without
> deleteding the instance.
> -Trevor
>
>
> > -----Original Message-----
> > From: zope-admin@zope.org [mailto:zope-admin@zope.org]On Behalf Of Max M
> > Sent: Monday, October 22, 2001 3:44 PM
> > To: Zope@Zope. Org
> > Subject: [Zope] [ADVANCED] How do YOU guys do many-to-many in Zope
> > without relational?
> >
> >
> > I am in the situation where I have to do what corresponds to a
> > many-to-many
> > relation in Zope.
> >
> > I basically have two zClassses. students and subjects. There can be many
> > subjects, and in any subject there can be any number of students.
> >
> > What I do now is having a studentlist under each subject. But
> this doesn't
> > really work because any single student can belong to any number
> > of subjects.
> >
> > So if this was an ordinary relational db it would be many to many.
> >
> > Now I considder making a global student list and then do a
> > recursive search
> > for subjects in the site, so that each student can be related
> to a subject
> > with a selectbox or somesuch.
> >
> > But if someone renames, deletes or moves a subject I am f.*?d Or
> > the student
> > is. The relation to the subject is invalidated.
> >
> > I have never seen it used, but would it be possible to store the "global
> > object id" in a list in a user object, and then get the path to
> > the subject
> > object from that?
> >
> > Or should I make the subject a global list to? That way I only
> > have to check
> > if the object exists or not. Not where it is in the object hierachy.
> >
> > This sort of defeats the purpose of Zope's tree like structure.
> > Doesn't it?
> >
> > So, how do YOU guys do many-to-many in Zope ?
> >
> > regards Max M
> >
> > Max M. W. Rasmussen,    Denmark.   New Media Director
> > private: maxmcorp@worldonline.dk work: maxm@normik.dk
> > -----------------------------------------------------
> > Shipping software is an unnatural act
> >
> >
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