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
23479	makemigrations geterates wrong migration for ForeignKey to unmanaged model	Dmitri Bogomolov	nobody	"I wrote a simple test app:
{{{#!python
from django.db import models


class Obj(models.Model):
    custom_named_id = models.IntegerField(
        primary_key=True, db_column='custom_named_id'  # not needed and doesn't help
    )
    field_2 = models.CharField(max_length=10, null=True, blank=True)

    class Meta:
        managed = False


class Pointer(models.Model):
    name = models.CharField(max_length=10, null=True, blank=True)
    obj = models.ForeignKey('Obj')

}}}

Migration generated for it will not work:
{{{#!sh
$ ./manage.py makemigrations migration_test
Migrations for 'migration_test':
  0001_initial.py:
    - Create model Pointer
    - Create model Obj
    - Add field obj to pointer
}}}

{{{#!sh
$ ./manage.py migrate migration_test
Operations to perform:
  Apply all migrations: migration_test
Running migrations:
  Applying migration_test.0001_initial...Traceback (most recent call last):
  File ""./manage.py"", line 12, in <module>
    execute_from_command_line(sys.argv)
  File ""/usr/lib/python2.7/site-packages/django/core/management/__init__.py"", line 385, in execute_from_command_line
    utility.execute()
  File ""/usr/lib/python2.7/site-packages/django/core/management/__init__.py"", line 377, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File ""/usr/lib/python2.7/site-packages/django/core/management/base.py"", line 288, in run_from_argv
    self.execute(*args, **options.__dict__)
  File ""/usr/lib/python2.7/site-packages/django/core/management/base.py"", line 338, in execute
    output = self.handle(*args, **options)
  File ""/usr/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 ""/usr/lib/python2.7/site-packages/django/db/migrations/executor.py"", line 63, in migrate
    self.apply_migration(migration, fake=fake)
  File ""/usr/lib/python2.7/site-packages/django/db/migrations/executor.py"", line 97, in apply_migration
    migration.apply(project_state, schema_editor)
  File ""/usr/lib/python2.7/site-packages/django/db/backends/schema.py"", line 82, in __exit__
    self.execute(sql)
  File ""/usr/lib/python2.7/site-packages/django/db/backends/schema.py"", line 98, in execute
    cursor.execute(sql, params)
  File ""/usr/lib/python2.7/site-packages/django/db/backends/utils.py"", line 81, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File ""/usr/lib/python2.7/site-packages/django/db/backends/utils.py"", line 65, in execute
    return self.cursor.execute(sql, params)
  File ""/usr/lib/python2.7/site-packages/django/db/utils.py"", line 94, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File ""/usr/lib/python2.7/site-packages/django/db/backends/utils.py"", line 65, in execute
    return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: column ""id"" referenced in foreign key constraint does not exist
}}}

It happens because migrate generates SQL with wrong constraint:

{{{#!sh
$ ./manage.py sqlmigrate migration_test 0001
BEGIN;
CREATE TABLE ""migration_test_pointer"" (""id"" serial NOT NULL PRIMARY KEY, ""name"" varchar(10) NULL);
ALTER TABLE ""migration_test_pointer"" ADD COLUMN ""obj_id"" integer NOT NULL;
ALTER TABLE ""migration_test_pointer"" ALTER COLUMN ""obj_id"" DROP DEFAULT;
CREATE INDEX migration_test_pointer_818ad5ef ON ""migration_test_pointer"" (""obj_id"");
ALTER TABLE ""migration_test_pointer"" ADD CONSTRAINT migration_test_pointer_obj_id_7e364e33_fk_migration_test_obj_id FOREIGN KEY (""obj_id"") REFERENCES ""migration_test_obj"" (""id"") DEFERRABLE INITIALLY DEFERRED;

COMMIT;
}}}"	Uncategorized	closed	Migrations	1.7	Normal	duplicate			Unreviewed	0	0	0	0	0	0