I have two models which are associated to each other through a ForeignKey how to delete the child model object without affecting parent model object

[Vignesh s]

I have two models which are associated to each other through a ForeignKey how to delete the child model object without affecting parent model object

[Jordan Micle]

when you use foreingkey you will set these options

here, change like this

on_delete=models.SET_NULL 

user = models.ForeignKey(User, null=True, on_delete=models.SET_NULL)

[Nijo Joseph]

Since you are deleting the child model object none of these matters. But if you are deleting the parent model object on_delete matters.

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[Parth Joshi]

Agree with Jordan. When you talk about CASCADE Delete to SET_NULL, those will matter when the parent table is deleted.

For Example:

User

Field	Type
UserID	INT
Username	VARCHAR

Employee

Field	Type	Relationship
… some fields
User	INT	Foreignkey(User, Userid)

In this case:

1. If you delete Employee with a related User, you don’t have to worry about cascading on User.

2. But if you delete a User, the User is already referred in multiple places in other tables. Deleting that user will create a dangling reference. Which will affect the integrity constraints. So here you set a policy to DELETE on cascade or SET_NULL on related fields. 

Hope this helps

Regards, 

Parth Joshi

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