Django on delete set default

It depends on your business requirements. Should every Item always point to a valid Policy? And what's the requirement from business point-of-view when a Policy gets deleted? Should the Items pointing to it also be deleted? We don't know your requirements, so it's difficult to answer your question. These are your options from a technical perspective:

Set on_delete=CASCADE if you want the Item to be deleted when the Policy is deleted
Set on_delete=PROTECT if you don't want to allow any Policy to be deleted if there's still any Item pointing to it. In that case you'll have to try: policy.delete(); except ProtectedError: ... in your code to handle that situation.
Set on_delete=SET_DEFAULT if you know your default policy will not be deleted (you could override the delete method on Policy to avoid deleting the default policy).
Set on_delete=SET_NULL if an Item can have no Policy. That may be valid in certain business scenarios. But in this case you must also have null=True.

Similar codes

0 vote257 views1 answer
Django override form fields in admin
Python Django
0 vote196 views1 answer
Convert any .pdf file into audio python dev.to
Python
-1 vote243 views1 answer
Django email verification
Python Django
78 votes187 views4 answers
Read json
Python
0 vote211 views2 answers
Where should favicon.ico be placed in flask app
Python
15 votes230 views2 answers
Pandas get all rows with value
Python
0 vote266 views2 answers
Python unsupported operand type(s) for & 'str' and 'str'
Python
3 votes181 views2 answers
Encryption using python
Python
1 vote207 views1 answer
Python write txt utf8
Python
0 vote191 views1 answer
Time now random seed python
Python