Here's the link to the PR for review: https://github.com/django/django/pull/11899
(Apologies for the double-post) - David On Sunday, October 13, 2019 at 3:37:07 PM UTC-7, David Foster wrote: > > I've created a PR which is waiting for review, if someone has time. > > According to Trac, the next step is: > > For anyone except the patch author to review the patch using the patch > review checklist > <https://docs.djangoproject.com/en/dev/internals/contributing/writing-code/submitting-patches/#patch-review-checklist> > and > either mark the ticket as "Ready for checkin" if everything looks good, or > leave comments for improvement and mark the ticket as "Patch needs > improvement". > > Thanks for any help. > > - David > > On Tuesday, October 1, 2019 at 11:06:15 PM UTC-7, David Foster wrote: >> >> Trac ticket created: https://code.djangoproject.com/ticket/30828 >> >> On Tuesday, October 1, 2019 at 3:02:38 AM UTC-7, Tom Forbes wrote: >>> >>> Hey David, >>> I like this idea, while I don’t think the use case is common there have >>> been a few times where I’ve needed this and got around it by >>> creating/modifying the through model in bulk. Having a method that does >>> this would be good IMO. >>> >>> Unless anyone has strong opinions against this then can you make a >>> ticket? >>> >>> Tom >>> >>> On 30 Sep 2019, at 02:14, David Foster <davi...@gmail.com> wrote: >>> >>> >>> Here is another API variation I might suggest: >>> >>> M1.m2_set.add_pairs(*[(m1, m2), ...], assert_no_collisions=False) >>> # --- OR --- >>> M1.m2_set.add_pair_ids(*[(m1_id, m2_id), ...], assert_no_collisions= >>> False) >>> >>> This has the advantages of being more similar to the existing add() API >>> and not requiring a special function import. >>> >>> For bulk_disassociate() the analogous API would be: >>> >>> M1.m2_set.remove_pairs(*[(m1, m2), ...]) >>> # --- OR --- >>> M1.m2_set.remove_pair_ids(*[(m1_id, m2_id), ...]) >>> >>> - David >>> >>> On Thursday, September 26, 2019 at 10:45:45 AM UTC-7, David Foster wrote: >>>> >>>> Given the following example model: >>>> >>>> class M1(models.Model): >>>> m2_set = models.ManyToManyField('M2') >>>> >>>> It is already possible to associate *one* M1 with *many* M2s with a >>>> single DB query: >>>> >>>> m1.m2_set.add(*m2s) >>>> >>>> However it's more difficult to associate *many* M1s with *many* M2s, >>>> particularly if you want to skip associations that already exist. >>>> >>>> # NOTE: Does NOT skip associations that already exist! >>>> m1_and_m2_id_tuples = [(m1_id, m2_id), ...] >>>> M1_M2 = M1.m2_set.through >>>> M1_M2.objects.bulk_create([ >>>> M1_M2(m1_id=m1_id, m2_id=m2_id) >>>> for (m1_id, m2_id) in >>>> m1_and_m2_id_tuples >>>> ]) >>>> >>>> What if we could do something like the following instead: >>>> >>>> bulk_associate(M1.m2_set, [(m1, m2), ...]) >>>> # --- OR --- >>>> bulk_associate_ids(M1.m2_set, [(m1_id, m2_id), ...]) >>>> >>>> I propose to write and add a *bulk_associate()* method to Django. I >>>> also propose to add a paired *bulk_disassociate()* method. >>>> >>>> *1. Does this sound like a good idea in general?* >>>> >>>> >>>> In more detail, I propose adding the specific APIs, importable from >>>> *django.db*: >>>> >>>> M1 = TypeVar('M1', bound=Model) # M1 extends Model >>>> M2 = TypeVar('M2', bound=Model) # M2 extends Model >>>> >>>> def bulk_associate( >>>> M1_m2_set: ManyToManyDescriptor, >>>> m1_m2_tuples: 'List[Tuple[M1, M2]]', >>>> *, assert_no_collisions: bool=True) -> None: >>>> """ >>>> Creates many (M1, M2) associations with O(1) database queries. >>>> >>>> If any requested associations already exist, then they will be left >>>> alone. >>>> >>>> If you assert that none of the requested associations already exist, >>>> you can pass assert_no_collisions=True to save 1 database query. >>>> """ >>>> pass >>>> >>>> def bulk_associate_ids( >>>> M1_m2_set: ManyToManyDescriptor, >>>> m1_m2_id_tuples: 'List[Tuple[Any, Any]]', >>>> *, assert_no_collisions: bool=True) -> None: >>>> pass >>>> >>>> If assert_no_collisions is False then (1 filter) query and (1 >>>> bulk_create) query will be performed. >>>> If assert_no_collisions is True then only (1 bulk_create) will be >>>> performed. >>>> >>>> def bulk_disassociate( >>>> M1_m2_set: ManyToManyDescriptor, >>>> m1_m2_tuples: 'List[Tuple[M1, M2]]') -> None: >>>> """ >>>> Deletes many (M1, M2) associations with O(1) database queries. >>>> """ >>>> pass >>>> >>>> def bulk_disassociate_ids( >>>> M1_m2_set: ManyToManyDescriptor, >>>> m1_m2_id_tuples: 'List[Tuple[Any, Any]]') -> None: >>>> pass >>>> >>>> The database connection corresponding to the M1_M2 through-table will >>>> be used. >>>> >>>> *2. Any comments on the specific API or capabilities?* >>>> >>>> >>>> If this sounds good I'd be happy to open an item on Trac and submit a >>>> PR. >>>> >>> -- >>> 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-d...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/django-developers/49b45d05-836f-4512-91b8-8e4dbb55f6a4%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/django-developers/49b45d05-836f-4512-91b8-8e4dbb55f6a4%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. 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