Opened 7 years ago

Last modified 6 years ago

#28514 closed Cleanup/optimization

Clarify docs regarding idempotence of RelatedManager.add() — at Version 1

Reported by: Дилян Палаузов Owned by: nobody
Component: Documentation Version: 1.11
Severity: Normal Keywords:
Cc: Triage Stage: Accepted
Has patch: yes Needs documentation: no
Needs tests: no Patch needs improvement: yes
Easy pickings: yes UI/UX: no

Description (last modified by Tim Graham)

At ​https://docs.djangoproject.com/en/1.11/topics/db/examples/many_to_many/ it's written:

>> a2.publications.add(p3)
>
> Adding a second time is OK:
> 
>> a2.publications.add(p3)

Please rephrase it to "Adding a second time is OK, it doesn't duplicate the relation".

At ​https://docs.djangoproject.com/en/1.11/ref/models/relations/ it's written:

 add(*objs, bulk=True)
 Adds the specified model objects to the related object set.

Please amend: "Inserting existing relations this way does not cause problems."

The purpose of the changes is to make clear, that add() is idempotent and it is not necessary first to read the data from the database, join with the new values and eventually write the resulting set back.

Change History (1)

comment:1 by Tim Graham, 7 years ago

Description: modified (diff)
Easy pickings: set
Summary: Documentating idempotence of Many2ManyField.add() → Clarify docs regarding idempotence of RelatedManager.add()
Triage Stage: Unreviewed → Accepted
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