If you are familiar with Django, you know that they have a Authentication system with User model
. Of course, I have many other tables that have a Foreign Key to this User
model.
If I want to delete this user, how do I architect开发者_运维问答 a script (or through mysql itself) to delete every table that is related to this user?
My only worry is that I can do this manually...but if I add a table , but I forget to add that table to my DELETE operation...then I have a row that links to a deleted, non-existing User.
As far as I understand it, django does an "on delete cascade" by default: http://docs.djangoproject.com/en/dev/topics/db/queries/#deleting-objects
You don't need a script for this. When you delete a record, Django will automatically delete all dependent records (thus taking care of its own database integrity).
This is simple to test. In the admin, go to delete a User. On the confirmation page, you'll see a list of all dependent records in the system. You can use this any time as a quick test to see what's dependent on what (as long as you don't actually click Confirm).
If you perform deletions from your view code with .delete()
, all dependent objects will be deleted automatically with no option for confirmation.
From the docs:
When Django deletes an object, it emulates the behavior of the SQL constraint ON DELETE CASCADE -- in other words, any objects which had foreign keys pointing at the object to be deleted will be deleted along with it.
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