Python django.db.connection.schema_editor() Examples

def test_delete_model(self):
        """
        Tests the DeleteModel operation.
        """
        project_state = self.set_up_test_model("test_dlmo")
        # Test the state alteration
        operation = migrations.DeleteModel("Pony")
        self.assertEqual(operation.describe(), "Delete model Pony")
        new_state = project_state.clone()
        operation.state_forwards("test_dlmo", new_state)
        self.assertNotIn(("test_dlmo", "pony"), new_state.models)
        # Test the database alteration
        self.assertTableExists("test_dlmo_pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dlmo", editor, project_state, new_state)
        self.assertTableNotExists("test_dlmo_pony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dlmo", editor, new_state, project_state)
        self.assertTableExists("test_dlmo_pony")
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "DeleteModel")
        self.assertEqual(definition[1], [])
        self.assertEqual(list(definition[2]), ["name"]) 

def test_alter_field_with_index(self):
        """
        Test AlterField operation with an index to ensure indexes created via
        Meta.indexes don't get dropped with sqlite3 remake.
        """
        project_state = self.set_up_test_model("test_alflin", index=True)
        operation = migrations.AlterField("Pony", "pink", models.IntegerField(null=True))
        new_state = project_state.clone()
        operation.state_forwards("test_alflin", new_state)
        # Test the database alteration
        self.assertColumnNotNull("test_alflin_pony", "pink")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_alflin", editor, project_state, new_state)
        # Index hasn't been dropped
        self.assertIndexExists("test_alflin_pony", ["pink"])
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_alflin", editor, new_state, project_state)
        # Ensure the index is still there
        self.assertIndexExists("test_alflin_pony", ["pink"]) 

def test_alter_field_pk(self):
        """
        Tests the AlterField operation on primary keys (for things like PostgreSQL's SERIAL weirdness)
        """
        project_state = self.set_up_test_model("test_alflpk")
        # Test the state alteration
        operation = migrations.AlterField("Pony", "id", models.IntegerField(primary_key=True))
        new_state = project_state.clone()
        operation.state_forwards("test_alflpk", new_state)
        self.assertIsInstance(project_state.models["test_alflpk", "pony"].get_field_by_name("id"), models.AutoField)
        self.assertIsInstance(new_state.models["test_alflpk", "pony"].get_field_by_name("id"), models.IntegerField)
        # Test the database alteration
        with connection.schema_editor() as editor:
            operation.database_forwards("test_alflpk", editor, project_state, new_state)
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_alflpk", editor, new_state, project_state) 

def test_remove_fk(self):
        """
        Tests the RemoveField operation on a foreign key.
        """
        project_state = self.set_up_test_model("test_rfk", related_model=True)
        self.assertColumnExists("test_rfk_rider", "pony_id")
        operation = migrations.RemoveField("Rider", "pony")

        new_state = project_state.clone()
        operation.state_forwards("test_rfk", new_state)
        with connection.schema_editor() as editor:
            operation.database_forwards("test_rfk", editor, project_state, new_state)
        self.assertColumnNotExists("test_rfk_rider", "pony_id")
        with connection.schema_editor() as editor:
            operation.database_backwards("test_rfk", editor, new_state, project_state)
        self.assertColumnExists("test_rfk_rider", "pony_id") 

def setUp(self):
        # Create a dummy model which extends the mixin. A RuntimeWarning will
        # occur if the model is registered twice
        if not hasattr(self, 'model'):
            self.model = ModelBase(
                '__TestModel__' +
                self.mixin.__name__, (self.mixin,),
                {'__module__': self.mixin.__module__}
            )

        # Create the schema for our test model. If the table already exists,
        # will pass
        try:
            with connection.schema_editor() as schema_editor:
                schema_editor.create_model(self.model)
            super(AbstractModelMixinTestCase, self).setUpClass()
        except ProgrammingError:
            pass 

def get_fake_model(fields=None, model_base=LocalizedModel, meta_options={}):
    """Creates a fake model to use during unit tests."""

    model = define_fake_model(fields, model_base, meta_options)

    class TestProject:
        def clone(self, *_args, **_kwargs):
            return self

        @property
        def apps(self):
            return self

    class TestMigration(migrations.Migration):
        operations = [HStoreExtension()]

    with connection.schema_editor() as schema_editor:
        migration_executor = MigrationExecutor(schema_editor.connection)
        migration_executor.apply_migration(
            TestProject(), TestMigration("eh", "postgres_extra")
        )

        schema_editor.create_model(model)

    return model 

def _test_run_python(self, app_label, should_run, hints=None):
        with override_settings(DATABASE_ROUTERS=[MigrateEverythingRouter()]):
            project_state = self.set_up_test_model(app_label)

        # Create the operation
        def inner_method(models, schema_editor):
            Pony = models.get_model(app_label, "Pony")
            Pony.objects.create(pink=1, weight=3.55)
            Pony.objects.create(weight=5)

        operation = migrations.RunPython(inner_method, hints=hints or {})
        # Test the state alteration does nothing
        new_state = project_state.clone()
        operation.state_forwards(app_label, new_state)
        self.assertEqual(new_state, project_state)
        # Test the database alteration
        self.assertEqual(project_state.apps.get_model(app_label, "Pony").objects.count(), 0)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, project_state, new_state)
        Pony = project_state.apps.get_model(app_label, "Pony")
        if should_run:
            self.assertEqual(Pony.objects.count(), 2)
        else:
            self.assertEqual(Pony.objects.count(), 0) 

def _test_run_sql(self, app_label, should_run, hints=None):
        with override_settings(DATABASE_ROUTERS=[MigrateEverythingRouter()]):
            project_state = self.set_up_test_model(app_label)

        sql = """
        INSERT INTO {0}_pony (pink, weight) VALUES (1, 3.55);
        INSERT INTO {0}_pony (pink, weight) VALUES (3, 5.0);
        """.format(app_label)

        operation = migrations.RunSQL(sql, hints=hints or {})
        # Test the state alteration does nothing
        new_state = project_state.clone()
        operation.state_forwards(app_label, new_state)
        self.assertEqual(new_state, project_state)
        # Test the database alteration
        self.assertEqual(project_state.apps.get_model(app_label, "Pony").objects.count(), 0)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, project_state, new_state)
        Pony = project_state.apps.get_model(app_label, "Pony")
        if should_run:
            self.assertEqual(Pony.objects.count(), 2)
        else:
            self.assertEqual(Pony.objects.count(), 0) 

def test_install_plugin(self):
        """
        Test we can load the example plugin that every version of MySQL ships
        with.
        """
        assert not plugin_exists("metadata_lock_info")

        state = ProjectState()
        operation = InstallPlugin("metadata_lock_info", "metadata_lock_info.so")
        assert (
            operation.describe()
            == "Installs plugin metadata_lock_info from metadata_lock_info.so"
        )
        new_state = state.clone()
        with connection.schema_editor() as editor:
            operation.database_forwards("testapp", editor, state, new_state)

        assert plugin_exists("metadata_lock_info")

        new_state = state.clone()
        with connection.schema_editor() as editor:
            operation.database_backwards("testapp", editor, new_state, state)

        assert not plugin_exists("metadata_lock_info") 

def test_install_soname(self):
        """
        Test we can load the 'metadata_lock_info' library.
        """
        assert not plugin_exists("metadata_lock_info")

        state = ProjectState()
        operation = InstallSOName("metadata_lock_info.so")
        assert operation.describe() == "Installs library metadata_lock_info.so"

        new_state = state.clone()
        with connection.schema_editor() as editor:
            operation.database_forwards("testapp", editor, state, new_state)
        assert plugin_exists("metadata_lock_info")

        new_state = state.clone()
        with connection.schema_editor() as editor:
            operation.database_backwards("testapp", editor, new_state, state)
        assert not plugin_exists("metadata_lock_info") 

def test_running_with_changes(self):
        project_state = self.set_up_test_model("test_arstd")
        operation = AlterStorageEngine("Pony", from_engine="MyISAM", to_engine="InnoDB")

        assert table_storage_engine("test_arstd_pony") == "MyISAM"

        # Forwards
        new_state = project_state.clone()
        operation.state_forwards("test_arstd", new_state)
        with connection.schema_editor() as editor:
            operation.database_forwards("test_arstd", editor, project_state, new_state)
        assert table_storage_engine("test_arstd_pony") == "InnoDB"

        # Backwards
        with connection.schema_editor() as editor:
            operation.database_backwards("test_arstd", editor, new_state, project_state)
        assert table_storage_engine("test_arstd_pony") == "MyISAM" 

def test_running_without_changes(self):
        project_state = self.set_up_test_model("test_arstd")
        operation = AlterStorageEngine("Pony", from_engine="MyISAM", to_engine="InnoDB")

        assert table_storage_engine("test_arstd_pony") == "InnoDB"

        # Forwards - shouldn't actually do an ALTER since it is already InnoDB
        new_state = project_state.clone()
        operation.state_forwards("test_arstd", new_state)
        capturer = CaptureQueriesContext(connection)
        with capturer, connection.schema_editor() as editor:
            operation.database_forwards("test_arstd", editor, project_state, new_state)
        queries = [q["sql"] for q in capturer.captured_queries]
        assert not any(q.startswith("ALTER TABLE ") for q in queries)
        assert table_storage_engine("test_arstd_pony") == "InnoDB"

        # Backwards - will actually ALTER since it is going 'back' to MyISAM
        with connection.schema_editor() as editor:
            operation.database_backwards("test_arstd", editor, new_state, project_state)
        assert table_storage_engine("test_arstd_pony") == "MyISAM"

    # Copied from django core migration tests 

def test_remove_field(self):
        """
        Tests the RemoveField operation.
        """
        project_state = self.set_up_test_model("test_rmfl")
        # Test the state alteration
        operation = migrations.RemoveField("Pony", "pink")
        self.assertEqual(operation.describe(), "Remove field pink from Pony")
        new_state = project_state.clone()
        operation.state_forwards("test_rmfl", new_state)
        self.assertEqual(len(new_state.models["test_rmfl", "pony"].fields), 2)
        # Test the database alteration
        self.assertColumnExists("test_rmfl_pony", "pink")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_rmfl", editor, project_state, new_state)
        self.assertColumnNotExists("test_rmfl_pony", "pink")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_rmfl", editor, new_state, project_state)
        self.assertColumnExists("test_rmfl_pony", "pink")
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "RemoveField")
        self.assertEqual(definition[1], [])
        self.assertEqual(definition[2], {'model_name': "Pony", 'name': 'pink'}) 

def _test_create_model(self, app_label, should_run):
        """
        CreateModel honors multi-db settings.
        """
        operation = migrations.CreateModel(
            "Pony",
            [("id", models.AutoField(primary_key=True))],
        )
        # Test the state alteration
        project_state = ProjectState()
        new_state = project_state.clone()
        operation.state_forwards(app_label, new_state)
        # Test the database alteration
        self.assertTableNotExists("%s_pony" % app_label)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, project_state, new_state)
        if should_run:
            self.assertTableExists("%s_pony" % app_label)
        else:
            self.assertTableNotExists("%s_pony" % app_label)
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards(app_label, editor, new_state, project_state)
        self.assertTableNotExists("%s_pony" % app_label) 

def test_delete_proxy_model(self):
        """
        Tests the DeleteModel operation ignores proxy models.
        """
        project_state = self.set_up_test_model("test_dlprmo", proxy_model=True)
        # Test the state alteration
        operation = migrations.DeleteModel("ProxyPony")
        new_state = project_state.clone()
        operation.state_forwards("test_dlprmo", new_state)
        self.assertIn(("test_dlprmo", "proxypony"), project_state.models)
        self.assertNotIn(("test_dlprmo", "proxypony"), new_state.models)
        # Test the database alteration
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_dlprmo", editor, project_state, new_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_dlprmo", editor, new_state, project_state)
        self.assertTableExists("test_dlprmo_pony")
        self.assertTableNotExists("test_dlprmo_proxypony") 

def test_add_field_ignore_swapped(self):
        """
        Tests the AddField operation.
        """
        # Test the state alteration
        operation = migrations.AddField(
            "Pony",
            "height",
            models.FloatField(null=True, default=5),
        )
        project_state, new_state = self.make_test_state("test_adfligsw", operation)
        # Test the database alteration
        self.assertTableNotExists("test_adfligsw_pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_adfligsw", editor, project_state, new_state)
        self.assertTableNotExists("test_adfligsw_pony")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_adfligsw", editor, new_state, project_state)
        self.assertTableNotExists("test_adfligsw_pony") 

def test_indexes_ignore_swapped(self):
        """
        Add/RemoveIndex operations ignore swapped models.
        """
        operation = migrations.AddIndex('Pony', models.Index(fields=['pink'], name='my_name_idx'))
        project_state, new_state = self.make_test_state('test_adinigsw', operation)
        with connection.schema_editor() as editor:
            # No database queries should be run for swapped models
            operation.database_forwards('test_adinigsw', editor, project_state, new_state)
            operation.database_backwards('test_adinigsw', editor, new_state, project_state)

        operation = migrations.RemoveIndex('Pony', models.Index(fields=['pink'], name='my_name_idx'))
        project_state, new_state = self.make_test_state("test_rminigsw", operation)
        with connection.schema_editor() as editor:
            operation.database_forwards('test_rminigsw', editor, project_state, new_state)
            operation.database_backwards('test_rminigsw', editor, new_state, project_state) 

def test_get_relations(self):
        with connection.cursor() as cursor:
            relations = connection.introspection.get_relations(cursor, Article._meta.db_table)

        # That's {field_name: (field_name_other_table, other_table)}
        expected_relations = {
            'reporter_id': ('id', Reporter._meta.db_table),
            'response_to_id': ('id', Article._meta.db_table),
        }
        self.assertEqual(relations, expected_relations)

        # Removing a field shouldn't disturb get_relations (#17785)
        body = Article._meta.get_field('body')
        with connection.schema_editor() as editor:
            editor.remove_field(Article, body)
        with connection.cursor() as cursor:
            relations = connection.introspection.get_relations(cursor, Article._meta.db_table)
        with connection.schema_editor() as editor:
            editor.add_field(Article, body)
        self.assertEqual(relations, expected_relations) 

def _test_run_python(self, app_label, should_run, hints=None):
        with override_settings(DATABASE_ROUTERS=[MigrateEverythingRouter()]):
            project_state = self.set_up_test_model(app_label)

        # Create the operation
        def inner_method(models, schema_editor):
            Pony = models.get_model(app_label, "Pony")
            Pony.objects.create(pink=1, weight=3.55)
            Pony.objects.create(weight=5)

        operation = migrations.RunPython(inner_method, hints=hints or {})
        # Test the state alteration does nothing
        new_state = project_state.clone()
        operation.state_forwards(app_label, new_state)
        self.assertEqual(new_state, project_state)
        # Test the database alteration
        self.assertEqual(project_state.apps.get_model(app_label, "Pony").objects.count(), 0)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, project_state, new_state)
        Pony = project_state.apps.get_model(app_label, "Pony")
        if should_run:
            self.assertEqual(Pony.objects.count(), 2)
        else:
            self.assertEqual(Pony.objects.count(), 0) 

def _test_run_sql(self, app_label, should_run, hints=None):
        with override_settings(DATABASE_ROUTERS=[MigrateEverythingRouter()]):
            project_state = self.set_up_test_model(app_label)

        sql = """
        INSERT INTO {0}_pony (pink, weight) VALUES (1, 3.55);
        INSERT INTO {0}_pony (pink, weight) VALUES (3, 5.0);
        """.format(app_label)

        operation = migrations.RunSQL(sql, hints=hints or {})
        # Test the state alteration does nothing
        new_state = project_state.clone()
        operation.state_forwards(app_label, new_state)
        self.assertEqual(new_state, project_state)
        # Test the database alteration
        self.assertEqual(project_state.apps.get_model(app_label, "Pony").objects.count(), 0)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, project_state, new_state)
        Pony = project_state.apps.get_model(app_label, "Pony")
        if should_run:
            self.assertEqual(Pony.objects.count(), 2)
        else:
            self.assertEqual(Pony.objects.count(), 0) 

def _test_create_model(self, app_label, should_run):
        """
        CreateModel honors multi-db settings.
        """
        operation = migrations.CreateModel(
            "Pony",
            [("id", models.AutoField(primary_key=True))],
        )
        # Test the state alteration
        project_state = ProjectState()
        new_state = project_state.clone()
        operation.state_forwards(app_label, new_state)
        # Test the database alteration
        self.assertTableNotExists("%s_pony" % app_label)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, project_state, new_state)
        if should_run:
            self.assertTableExists("%s_pony" % app_label)
        else:
            self.assertTableNotExists("%s_pony" % app_label)
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards(app_label, editor, new_state, project_state)
        self.assertTableNotExists("%s_pony" % app_label) 

def test_run_sql_params_invalid(self):
        """
        #23426 - RunSQL should fail when a list of statements with an incorrect
        number of tuples is given.
        """
        project_state = self.set_up_test_model("test_runsql")
        new_state = project_state.clone()
        operation = migrations.RunSQL(
            # forwards
            [
                ["INSERT INTO foo (bar) VALUES ('buz');"]
            ],
            # backwards
            (
                ("DELETE FROM foo WHERE bar = 'buz';", 'invalid', 'parameter count'),
            ),
        )

        with connection.schema_editor() as editor:
            with self.assertRaisesMessage(ValueError, "Expected a 2-tuple but got 1"):
                operation.database_forwards("test_runsql", editor, project_state, new_state)

        with connection.schema_editor() as editor:
            with self.assertRaisesMessage(ValueError, "Expected a 2-tuple but got 3"):
                operation.database_backwards("test_runsql", editor, new_state, project_state) 

def test_alter_fk_non_fk(self):
        """
        Altering an FK to a non-FK works (#23244)
        """
        # Test the state alteration
        operation = migrations.AlterField(
            model_name="Rider",
            name="pony",
            field=models.FloatField(),
        )
        project_state, new_state = self.make_test_state("test_afknfk", operation, related_model=True)
        # Test the database alteration
        self.assertColumnExists("test_afknfk_rider", "pony_id")
        self.assertColumnNotExists("test_afknfk_rider", "pony")
        with connection.schema_editor() as editor:
            operation.database_forwards("test_afknfk", editor, project_state, new_state)
        self.assertColumnExists("test_afknfk_rider", "pony")
        self.assertColumnNotExists("test_afknfk_rider", "pony_id")
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_afknfk", editor, new_state, project_state)
        self.assertColumnExists("test_afknfk_rider", "pony_id")
        self.assertColumnNotExists("test_afknfk_rider", "pony") 

def test_index_name(self):
        """
        Index names on the built-in database backends::
            * Are truncated as needed.
            * Include all the column names.
            * Include a deterministic hash.
        """
        long_name = 'l%sng' % ('o' * 100)
        with connection.schema_editor() as editor:
            index_name = editor._create_index_name(
                model=Article,
                column_names=('c1', 'c2', long_name),
                suffix='ix',
            )
        expected = {
            'mysql': 'indexes_article_c1_c2_looooooooooooooooooo_255179b2ix',
            'oracle': 'indexes_a_c1_c2_loo_255179b2ix',
            'postgresql': 'indexes_article_c1_c2_loooooooooooooooooo_255179b2ix',
            'sqlite': 'indexes_article_c1_c2_l%sng_255179b2ix' % ('o' * 100),
        }
        if connection.vendor not in expected:
            self.skipTest('This test is only supported on the built-in database backends.')
        self.assertEqual(index_name, expected[connection.vendor]) 

def test_alter_model_table_m2m(self):
        """
        AlterModelTable should rename auto-generated M2M tables.
        """
        app_label = "test_talflmltlm2m"
        pony_db_table = 'pony_foo'
        project_state = self.set_up_test_model(app_label, second_model=True, db_table=pony_db_table)
        # Add the M2M field
        first_state = project_state.clone()
        operation = migrations.AddField("Pony", "stables", models.ManyToManyField("Stable"))
        operation.state_forwards(app_label, first_state)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, project_state, first_state)
        original_m2m_table = "%s_%s" % (pony_db_table, "stables")
        new_m2m_table = "%s_%s" % (app_label, "pony_stables")
        self.assertTableExists(original_m2m_table)
        self.assertTableNotExists(new_m2m_table)
        # Rename the Pony db_table which should also rename the m2m table.
        second_state = first_state.clone()
        operation = migrations.AlterModelTable(name='pony', table=None)
        operation.state_forwards(app_label, second_state)
        with connection.schema_editor() as editor:
            operation.database_forwards(app_label, editor, first_state, second_state)
        self.assertTableExists(new_m2m_table)
        self.assertTableNotExists(original_m2m_table)
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards(app_label, editor, second_state, first_state)
        self.assertTableExists(original_m2m_table)
        self.assertTableNotExists(new_m2m_table) 

def test_separate_database_and_state(self):
        """
        Tests the SeparateDatabaseAndState operation.
        """
        project_state = self.set_up_test_model("test_separatedatabaseandstate")
        # Create the operation
        database_operation = migrations.RunSQL(
            "CREATE TABLE i_love_ponies (id int, special_thing int);",
            "DROP TABLE i_love_ponies;"
        )
        state_operation = migrations.CreateModel("SomethingElse", [("id", models.AutoField(primary_key=True))])
        operation = migrations.SeparateDatabaseAndState(
            state_operations=[state_operation],
            database_operations=[database_operation]
        )
        self.assertEqual(operation.describe(), "Custom state/database change combination")
        # Test the state alteration
        new_state = project_state.clone()
        operation.state_forwards("test_separatedatabaseandstate", new_state)
        self.assertEqual(len(new_state.models["test_separatedatabaseandstate", "somethingelse"].fields), 1)
        # Make sure there's no table
        self.assertTableNotExists("i_love_ponies")
        # Test the database alteration
        with connection.schema_editor() as editor:
            operation.database_forwards("test_separatedatabaseandstate", editor, project_state, new_state)
        self.assertTableExists("i_love_ponies")
        # And test reversal
        self.assertTrue(operation.reversible)
        with connection.schema_editor() as editor:
            operation.database_backwards("test_separatedatabaseandstate", editor, new_state, project_state)
        self.assertTableNotExists("i_love_ponies")
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "SeparateDatabaseAndState")
        self.assertEqual(definition[1], [])
        self.assertEqual(sorted(definition[2]), ["database_operations", "state_operations"]) 

def test_alter_order_with_respect_to(self):
        """
        Tests the AlterOrderWithRespectTo operation.
        """
        project_state = self.set_up_test_model("test_alorwrtto", related_model=True)
        # Test the state alteration
        operation = migrations.AlterOrderWithRespectTo("Rider", "pony")
        self.assertEqual(operation.describe(), "Set order_with_respect_to on Rider to pony")
        new_state = project_state.clone()
        operation.state_forwards("test_alorwrtto", new_state)
        self.assertIsNone(
            project_state.models["test_alorwrtto", "rider"].options.get("order_with_respect_to", None)
        )
        self.assertEqual(
            new_state.models["test_alorwrtto", "rider"].options.get("order_with_respect_to", None),
            "pony"
        )
        # Make sure there's no matching index
        self.assertColumnNotExists("test_alorwrtto_rider", "_order")
        # Create some rows before alteration
        rendered_state = project_state.apps
        pony = rendered_state.get_model("test_alorwrtto", "Pony").objects.create(weight=50)
        rendered_state.get_model("test_alorwrtto", "Rider").objects.create(pony=pony, friend_id=1)
        rendered_state.get_model("test_alorwrtto", "Rider").objects.create(pony=pony, friend_id=2)
        # Test the database alteration
        with connection.schema_editor() as editor:
            operation.database_forwards("test_alorwrtto", editor, project_state, new_state)
        self.assertColumnExists("test_alorwrtto_rider", "_order")
        # Check for correct value in rows
        updated_riders = new_state.apps.get_model("test_alorwrtto", "Rider").objects.all()
        self.assertEqual(updated_riders[0]._order, 0)
        self.assertEqual(updated_riders[1]._order, 0)
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_alorwrtto", editor, new_state, project_state)
        self.assertColumnNotExists("test_alorwrtto_rider", "_order")
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "AlterOrderWithRespectTo")
        self.assertEqual(definition[1], [])
        self.assertEqual(definition[2], {'name': "Rider", 'order_with_respect_to': "pony"}) 

def test_add_index(self):
        """
        Test the AddIndex operation.
        """
        project_state = self.set_up_test_model("test_adin")
        msg = (
            "Indexes passed to AddIndex operations require a name argument. "
            "<Index: fields='pink'> doesn't have one."
        )
        with self.assertRaisesMessage(ValueError, msg):
            migrations.AddIndex("Pony", models.Index(fields=["pink"]))
        index = models.Index(fields=["pink"], name="test_adin_pony_pink_idx")
        operation = migrations.AddIndex("Pony", index)
        self.assertEqual(operation.describe(), "Create index test_adin_pony_pink_idx on field(s) pink of model Pony")
        new_state = project_state.clone()
        operation.state_forwards("test_adin", new_state)
        # Test the database alteration
        self.assertEqual(len(new_state.models["test_adin", "pony"].options['indexes']), 1)
        self.assertIndexNotExists("test_adin_pony", ["pink"])
        with connection.schema_editor() as editor:
            operation.database_forwards("test_adin", editor, project_state, new_state)
        self.assertIndexExists("test_adin_pony", ["pink"])
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_adin", editor, new_state, project_state)
        self.assertIndexNotExists("test_adin_pony", ["pink"])
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "AddIndex")
        self.assertEqual(definition[1], [])
        self.assertEqual(definition[2], {'model_name': "Pony", 'index': index}) 

def test_run_sql_noop(self):
        """
        #24098 - Tests no-op RunSQL operations.
        """
        operation = migrations.RunSQL(migrations.RunSQL.noop, migrations.RunSQL.noop)
        with connection.schema_editor() as editor:
            operation.database_forwards("test_runsql", editor, None, None)
            operation.database_backwards("test_runsql", editor, None, None) 

def test_alter_index_together(self):
        """
        Tests the AlterIndexTogether operation.
        """
        project_state = self.set_up_test_model("test_alinto")
        # Test the state alteration
        operation = migrations.AlterIndexTogether("Pony", [("pink", "weight")])
        self.assertEqual(operation.describe(), "Alter index_together for Pony (1 constraint(s))")
        new_state = project_state.clone()
        operation.state_forwards("test_alinto", new_state)
        self.assertEqual(len(project_state.models["test_alinto", "pony"].options.get("index_together", set())), 0)
        self.assertEqual(len(new_state.models["test_alinto", "pony"].options.get("index_together", set())), 1)
        # Make sure there's no matching index
        self.assertIndexNotExists("test_alinto_pony", ["pink", "weight"])
        # Test the database alteration
        with connection.schema_editor() as editor:
            operation.database_forwards("test_alinto", editor, project_state, new_state)
        self.assertIndexExists("test_alinto_pony", ["pink", "weight"])
        # And test reversal
        with connection.schema_editor() as editor:
            operation.database_backwards("test_alinto", editor, new_state, project_state)
        self.assertIndexNotExists("test_alinto_pony", ["pink", "weight"])
        # And deconstruction
        definition = operation.deconstruct()
        self.assertEqual(definition[0], "AlterIndexTogether")
        self.assertEqual(definition[1], [])
        self.assertEqual(definition[2], {'name': "Pony", 'index_together': {("pink", "weight")}})