id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
23702	sqlite3 schema editor fails when altering a model's pk	Gavin Wahl	Tim Graham	"I changed the pk in my model from the implicit one to a custom one -- `id = models.BigIntegerField(primary_key=True)` -- and generated a migration:

{{{#!python
    operations = [
        migrations.AlterField(
            model_name='foo',
            name='id',
            field=models.BigIntegerField(serialize=False, primary_key=True),
        ),
    ]
}}}

This migration fails to run on sqlite:

{{{
Traceback (most recent call last):
  File ""./manage.py"", line 11, in <module>
    execute_from_command_line(sys.argv)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/core/management/__init__.py"", line 385, in execute_from_command_line
    utility.execute()
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/core/management/__init__.py"", line 377, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/core/management/base.py"", line 288, in run_from_argv
    self.execute(*args, **options.__dict__)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/core/management/base.py"", line 338, in execute
    output = self.handle(*args, **options)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/core/management/commands/migrate.py"", line 160, in handle
    executor.migrate(targets, plan, fake=options.get(""fake"", False))
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/db/migrations/executor.py"", line 63, in migrate
    self.apply_migration(migration, fake=fake)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/db/migrations/executor.py"", line 97, in apply_migration
    migration.apply(project_state, schema_editor)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/db/migrations/migration.py"", line 107, in apply
    operation.database_forwards(self.app_label, schema_editor, project_state, new_state)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/db/migrations/operations/fields.py"", line 139, in database_forwards
    schema_editor.alter_field(from_model, from_field, to_field)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/db/backends/schema.py"", line 473, in alter_field
    self._alter_field(model, old_field, new_field, old_type, new_type, old_db_params, new_db_params, strict)
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/db/backends/sqlite3/schema.py"", line 190, in _alter_field
    self._remake_table(model, alter_fields=[(old_field, new_field)])
  File ""/srv/python-environments/sb/local/lib/python2.7/site-packages/django/db/backends/sqlite3/schema.py"", line 78, in _remake_table
    del body[old_field.name]
KeyError: u'id'
}}}


Changing

{{{#!python
            del body[old_field.name]
            del mapping[old_field.column]
}}}

To 

{{{#!python
            body.pop(old_field.name, None)
            mapping.pop(old_field.column], None)
}}}

fixes the issue and the migration runs."	Bug	closed	Database layer (models, ORM)	1.7	Release blocker	fixed			Ready for checkin	1	0	0	0	0	0