Hi! I considered making `returning: bool` a flag that we are returning data. That would make it `Foo.objects.update(x=1, y=2, returning=True)` and avoid some footguns. Or even a new function (`update_returning`?) because I have mixed feelings about different return types based on parameters.
Returning fields other than ones updated is a valid case IMO: we can update some records and return the PKs of updated records for logging instead of having just the number of rows updated. Something like`.values_list('pk', flat=True)` is useful then. On Sat, Oct 7, 2023 at 6:46 PM Tom Carrick <t...@carrick.eu> wrote: > Hi Aivars, > > Since we spoke yesterday I've been thinking about this... > > I don't really see the value in returning a QuerySet. There are only a > limited number of options that make sense at this point, and even those are > tough to justify. Like what would happen if you do `Foo.objects.update(x=1, > returning=["x"]).values("y")`? > > I do see value in returning the model instances, though I feel there is a > potential footgun here where you can update a field, but not return it, so > you'd get the old value in the instance. Something like: > > `Foo.objects.update(x=1, y=2, returning=["x"])` > > Now you have updated y, but the model instance that gets returned still > has the old value. Maybe this is fine with a warning in the docs. > > I think regardless of what we do here, we should stick with the proposed > and roughly agreed upon API of having an extra argument to `update()` > rather than creating a new QuerySet method. > > Cheers, > Tom > > > On Tue, 3 Oct 2023 at 23:38, Plamedi klj <plamedikl...@gmail.com> wrote: > >> Bien >> >> Le lun. 25 sept. 2023 à 17:44, Aivars Kalvāns <aivars.kalv...@gmail.com> >> a écrit : >> >>> Hi! >>> >>> I want to implement these changes and I have a PR in the ticket >>> https://code.djangoproject.com/ticket/32406 >>> At the moment I have a new `update_returning` method but I can easily >>> replace it with ` (updates=None, *, returning:bool=None, **kwargs)` if you >>> decide to add functionality to the existing method instead. I did a search >>> on github and found only a single project with `returning` as model field. >>> However the returned value in my implementation is a `QuerySet` and I >>> can do `.get()`, `.only()`, `.defer()` and `.values()` or `.values_list()` >>> on that. Mainly because my use case is updating and refreshing the model in >>> a single database operation. The ticket has more examples. What do you >>> think, do you see any issues with this approach? >>> >>> trešdiena, 2021. gada 12. maijs 15:18:50 UTC+3 Tom Carrick rakstīja: >>> >>>> Apologies, I had totally forgotten about this, but I'm still interested >>>> in working on it, but still not sure about a few things. >>>> >>>> I've been thinking about the return value a bit. I can foresee cases >>>> where you wouldn't want the id returned. You might want the user to update >>>> something by slug, username, or some other identifier without revealing the >>>> IDs. Of course the user could reformat the return value however they like, >>>> but I don't see a reason to ask for something that isn't necessary. >>>> >>>> So I think a list of some kind of object (namedtuple or dict probably) >>>> makes the most sense to me. As for also adding the count, I am not sure. >>>> The return value would then be e.g. (1, [<data>]). I'm guessing this count >>>> would remain as the number of matched rows, rather than the updated ones - >>>> I am not sure if returning only gives back rows that were modified or not, >>>> the Postgres docs are at least unclear on this. If they're always going to >>>> be the same, I'm not sure there is much reason for returning the count when >>>> len(return_value) will do. >>>> >>>> I'm also not really sure on the data structure though. Namedtuples make >>>> the most sense to me but a dict might be useful for those wanting to shove >>>> this directly into JsonResponse, without needing _asdict(), for example. >>>> >>>> Cheers, >>>> Tom >>>> >>>> On Wed, 27 Jan 2021 at 10:45, Florian Apolloner <f.apo...@gmail.com> >>>> wrote: >>>> >>>>> Hi Simon, >>>>> >>>>> On Wednesday, January 27, 2021 at 5:54:42 AM UTC+1 charettes wrote: >>>>> >>>>>> I think that's the best option here if we want to elegantly add >>>>>> support for this feature while maintaining backward compability. >>>>>> Something >>>>>> along the lines of ... >>>>>> >>>>> >>>>> That is certainly an interesting approach. It kinda breaks the "there >>>>> should be one way of doing things" rule, but… >>>>> >>>>> The usage of `returning` bring another set of questions though. Since >>>>>> UPDATE are not ordered RETURNING data has little value without the >>>>>> primary >>>>>> key associated with the updated rows. Maybe the return value of >>>>>> `returning=[f1, ..., fn]` should be a dict mapping the primary key to >>>>>> list >>>>>> of returning values. >>>>>> >>>>> >>>>> I am not sure I like that. For things where you update just one row >>>>> and want to know the new values the primary key doesn't make much sense. >>>>> Granted for multiple rows it would maybe easier to have it automatically >>>>> keyed by the pk, but returning something always (the pk) without having an >>>>> option to disable it seems kinda wrong to me. Not sure what the best >>>>> option would be. >>>>> >>>>> Cheers, >>>>> Florian >>>>> >>>>> -- >>>>> >>>> You received this message because you are subscribed to the Google >>>>> Groups "Django developers (Contributions to Django itself)" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to django-develop...@googlegroups.com. >>>>> >>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/django-developers/4eea605a-57d7-4ce3-b233-3eb88c91e110n%40googlegroups.com >>>>> <https://groups.google.com/d/msgid/django-developers/4eea605a-57d7-4ce3-b233-3eb88c91e110n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Django developers (Contributions to Django itself)" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to django-developers+unsubscr...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/django-developers/ee284d47-6181-426d-98fd-3a0e50e0d9abn%40googlegroups.com >>> <https://groups.google.com/d/msgid/django-developers/ee284d47-6181-426d-98fd-3a0e50e0d9abn%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "Django developers (Contributions to Django itself)" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to django-developers+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/django-developers/CABZ%3D34ic1y%3D7J3hhsGDauVtfF0B6RW10htugQmD-mbE0sf%2BY_Q%40mail.gmail.com >> <https://groups.google.com/d/msgid/django-developers/CABZ%3D34ic1y%3D7J3hhsGDauVtfF0B6RW10htugQmD-mbE0sf%2BY_Q%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to a topic in the > Google Groups "Django developers (Contributions to Django itself)" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/django-developers/qQ5DT91nBLM/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > django-developers+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/CAHoz%3DMaWtPtsJhZp2m_am8acrOTkSHPzKZpP1iTf83PwxtUKGA%40mail.gmail.com > <https://groups.google.com/d/msgid/django-developers/CAHoz%3DMaWtPtsJhZp2m_am8acrOTkSHPzKZpP1iTf83PwxtUKGA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- Aivars -- You received this message because you are subscribed to the Google Groups "Django developers (Contributions to Django itself)" group. 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