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Changes between Initial Version and Version 1 of Ticket #24607, comment 16

initial	v1
1	1	new PR: https://github.com/django/django/pull/8370
2	2
3		I slightly reworked @jpmelos earlier PR #7231 to hopefully avoid the problem with spurious migrations. When a parent link is being promoted as a pk, I don't modify that field, but I take note of the promotion in the inheriting model's _meta (well, Options actually, but that ends up the same). Then a field is always serialized if it has been promoted, even if it is marked `serialize=False`.
	3	I slightly reworked @jpmelos earlier PR #7231 to hopefully avoid the problem with spurious migrations. When a relation with `parent_link=True` is used as a pk then, when serializing with natural primary keys, the field must be serialized, even when marked with `serialize=False`.