Commit f4f0060f authored by Jean-Louis Fuchs's avatar Jean-Louis Fuchs Committed by Markus Holtermann
Browse files

Fixed #24447 -- Made migrations add FK constraints for existing columns 

When altering from e.g. an IntegerField to a ForeignKey, Django didn't
add a constraint.
parent c36b6083

django/db/backends/base/schema.py

+3 −3
Original line number Diff line number Diff line
@@ -709,9 +709,9 @@ class BaseDatabaseSchemaEditor(object): 
                }

            )

        # Does it have a foreign key?

        if new_field.rel and \

           (fks_dropped or (old_field.rel and not old_field.db_constraint)) and \

           new_field.db_constraint:

        if (new_field.rel and

                (fks_dropped or not old_field.rel or not old_field.db_constraint) and

                new_field.db_constraint):

            self.execute(self._create_fk_sql(model, new_field, "_fk_%(to_table)s_%(to_column)s"))

        # Rebuild FKs that pointed to us if we previously had to drop them

        if old_field.primary_key and new_field.primary_key and old_type != new_type:

docs/releases/1.7.6.txt

+2 −1
Original line number Diff line number Diff line
@@ -9,4 +9,5 @@ Django 1.7.6 fixes several bugs in 1.7.5. 
Bugfixes

========



* ...
 
* Fixed a bug that prevented migrations from adding a FK constraint

  for an existing column. (:ticket:`24447`).

tests/schema/tests.py

+39 −0
Original line number Diff line number Diff line
@@ -545,6 +545,45 @@ class SchemaTests(TransactionTestCase): 
        else:

            self.fail("No FK constraint for author_id found")



    @unittest.skipUnless(connection.features.supports_foreign_keys, "No FK support")

    def test_alter_to_fk(self):

        """

        #24447 - Tests adding a FK constraint for an existing column

        """

        class LocalBook(Model):

            author = IntegerField()

            title = CharField(max_length=100, db_index=True)

            pub_date = DateTimeField()



            class Meta:

                app_label = 'schema'

                apps = new_apps



        self.local_models = [LocalBook]



        # Create the tables

        with connection.schema_editor() as editor:

            editor.create_model(Author)

            editor.create_model(LocalBook)

        # Ensure no FK constraint exists

        constraints = self.get_constraints(LocalBook._meta.db_table)

        for name, details in constraints.items():

            if details['foreign_key']:

                self.fail('Found an unexpected FK constraint to %s' % details['columns'])

        old_field = LocalBook._meta.get_field("author")

        new_field = ForeignKey(Author)

        new_field.set_attributes_from_name("author")

        with connection.schema_editor() as editor:

            editor.alter_field(LocalBook, old_field, new_field, strict=True)

        constraints = self.get_constraints(LocalBook._meta.db_table)

        # Ensure FK constraint exists

        for name, details in constraints.items():

            if details['foreign_key'] and details['columns'] == ["author_id"]:

                self.assertEqual(details['foreign_key'], ('schema_author', 'id'))

                break

        else:

            self.fail("No FK constraint for author_id found")



    @unittest.skipUnless(connection.features.supports_foreign_keys, "No FK support")

    def test_alter_o2o_to_fk(self):

        """