[X] This cannot be dealt with as a third party library. (We prefer new functionality to be in the form of third party libraries where possible.)
[X] I have reduced the issue to the simplest possible case.
If you have a database unique constraint that includes a nullable field, DRF will still raise an 'field_A and field_B must make a unique set' validationerror when you try to post a new nullable field. Whereas on database level every NULL is considered unique.
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If you have a database unique constraint that includes a nullable field, DRF will still raise an 'field_A and field_B must make a unique set' validationerror when you try to post a new nullable field. Whereas on database level every NULL is considered unique.
Could be fixed maybe here in the code: https://github.com/encode/django-rest-framework/blob/63063da0820e23ef0edbf92a3031103a6c2ce254/rest_framework/validators.py#L123