How do I remove an email from a Django User?

Question

I have a Django webapp in which users register, login, logout as usual. When a user "Deletes" their account, I don't actually want to delete it (because it has foreign keys pointing to it). I just want to mark the User.is_active = False. I also would like to remove the email address (but not the username) so that the person can create a new account with the same email address. How to do it?

As you can see below, when I try to remove the email address from a User, it disallows me from doing so. If this operation really is not allowed, then how do other people solve this problem of wanting to allow deleted users to re-register with the same email address? I guess I could just change the email address to some dummy value like [email protected], but that seems really ugly.

>>> from django.contrib.auth.models import User
>>> x = User.objects.get(username="someuser")
>>> x.email = None
>>> x.save()
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/models/base.py", line 591, in save
    force_update=force_update, update_fields=update_fields)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/models/base.py", line 619, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/models/base.py", line 681, in _save_table
    forced_update)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/models/base.py", line 725, in _do_update
    return filtered._update(values) > 0
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/models/query.py", line 600, in _update
    return query.get_compiler(self.db).execute_sql(CURSOR)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 1004, in execute_sql
    cursor = super(SQLUpdateCompiler, self).execute_sql(result_type)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 786, in execute_sql
    cursor.execute(sql, params)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/backends/utils.py", line 81, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/backends/utils.py", line 65, in execute
    return self.cursor.execute(sql, params)
  File "MyVirtualEnv/lib/python2.7/site-packages/django/db/backends/mysql/base.py", line 128, in execute
    return self.cursor.execute(query, args)
  File "MyVirtualEnv/lib/python2.7/site-packages/MySQLdb/cursors.py", line 207, in execute
    if not self._defer_warnings: self._warning_check()
  File "MyVirtualEnv/lib/python2.7/site-packages/MySQLdb/cursors.py", line 117, in _warning_check
    warn(w[-1], self.Warning, 3)
Warning: Column 'email' cannot be null

Answer 1

From this question: https://stackoverflow.com/a/29810311/2800876

In Django, a User is defined as follows:

email = models.EmailField(_('email address'), blank=True)

Consequently, a user's email can be blank (i.e. "") but not null (i.e. None). You clear a user's email with the following:

user.email = ""
user.save()