Using many to many relationship will work better. Nice note ๐ค Your quote Translation : "ูุง ูุคู ู ุงุญุฏูู ุญุชู ูุญุจ ูุงุฎูู ู ุง ูุญุจ ูููุณู" On 27 Jul 2022 19:04, "Malik Rumi" <[email protected]> wrote:
> Thanks, but the recursive foreignkey *is* a one to many relationship... > unless you're talking about something else? > *โNone of you has faith until he loves for his brother or his neighbor > what he loves for himself.โ* > > > On Wed, Jul 27, 2022 at 10:16 AM Ammar Mohammed <[email protected]> > wrote: > >> Hi >> Have you tried using OneToMany relationship ? >> On 27 Jul 2022 12:18, "Malik Rumi" <[email protected]> wrote: >> >>> I have a model with a recursive foreign key to 'self'. This is intended >>> to model a parent child >>> relation among instances. The forward relation, on a field called >>> 'childof', works as expected. >>> The reverse relation, using the related_name 'parent', comes up as a >>> RelatedManager, >>> again as expected. However, parent.count(), parent.all(), etc., always >>> give me the "Manager is >>> not accessible on instances" error. Many of these parent instances will >>> themselves also be a >>> childof some other instance, and apparently, that's my problem. I don't >>> know how to make Django >>> recognize the dual nature of some instances. Is there a way to hack the >>> RelatedManager to fix this? >>> >>> I am not getting any accessor errors from manage.py check. >>> >>> I posted this to Django Forum, but the respondent was not able to >>> duplicate my issue - i.e., >>> he said it worked as expected for him. :-( >>> >>> I saw a suggestion to use an explicit junction table on Stack Overflow, >>> but making a round trip - or two - to an external table seems like an >>> awful lot of overhead for this situation. >>> >>> If instead of a junction table, if I made an explicit parentto field on >>> the model, would that work? >>> Presumably the related name on the childof field would still fail like >>> it does now, >>> but I would instead have the explicit parent field to work with. I still >>> would not have the >>> automatic reverse relation, and I would have to come up with a script to >>> fill in the parentto >>> field, but that might solve my problem: >>> # pseudocode >>> family = c.itertools.groupby(instance.childof) >>> family = c.pandas.groupby(instance.childof) >>> for f in family: >>> pop = c.objects.get(instance.childof) >>> OR >>> pop = instance.childof >>> c.objects.update(pop.parentto=f) # where parentto is a Postgresql >>> ArrayField >>> OR # https://docs.djangoproject.com/en/4.0/ref/models/ >>> relations/#django.db.models >>> .fields.related.RelatedManager.add: >>> >>> b = Blog.objects.get(id=1) >>> >>> e = Entry.objects.get(id=234) >>> >>> b.entry_set.add(e) # Associates Entry e with Blog b >>> SEE ALSO: https://docs.djangoproject.com/en/4.0/topics/db/examples/ >>> many_to_one/ >>> >>> If I did this two field hack, then I don't really need either one to be >>> ForeignKeys any more, >>> do I? They could be a CharField and an ArrayField, couldn't they? That >>> breaks the extended >>> lookup chain - but I don't have that now, anyway - or at least, I only >>> have it in one direction. >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Django users" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit https://groups.google.com/d/ >>> msgid/django-users/3555d391-9c9e-440f-a603-103c9ccdc858n% >>> 40googlegroups.com >>> <https://groups.google.com/d/msgid/django-users/3555d391-9c9e-440f-a603-103c9ccdc858n%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> You received this message because you are subscribed to a topic in the >> Google Groups "Django users" group. >> To unsubscribe from this topic, visit https://groups.google.com/d/ >> topic/django-users/xGtwxhx2Nrw/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> To view this discussion on the web visit https://groups.google.com/d/ >> msgid/django-users/CAHs1H7tjom_GRucP8Dx3x8AzQobS4GCva8a0nuN3b >> EWVB2Taqw%40mail.gmail.com >> <https://groups.google.com/d/msgid/django-users/CAHs1H7tjom_GRucP8Dx3x8AzQobS4GCva8a0nuN3bEWVB2Taqw%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to the Google Groups > "Django users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit https://groups.google.com/d/ > msgid/django-users/CAKd6oBxYfR6ntzGe8EGbnm0z6%2BxjiJDP5nmg9kF5kuB9pCZiEg% > 40mail.gmail.com > <https://groups.google.com/d/msgid/django-users/CAKd6oBxYfR6ntzGe8EGbnm0z6%2BxjiJDP5nmg9kF5kuB9pCZiEg%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Django users" group. 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