Commit 4480645a authored by Malcolm Tredinnick's avatar Malcolm Tredinnick
Browse files

Fixed #8316 -- Put tighter restrictions on the type of Foreign Key fields 

created for MySQL (because MySQL + InnoDB has those restrictions).
Patch from julianb.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@8782 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent 032d6549

django/db/backends/__init__.py

+3 −0
Original line number Diff line number Diff line
@@ -71,6 +71,9 @@ class BaseDatabaseFeatures(object): 
    interprets_empty_strings_as_nulls = False

    can_use_chunked_reads = True

    uses_savepoints = False

    # If True, don't use integer foreign keys referring to, e.g., positive

    # integer primary keys.

    related_fields_match_type = False



class BaseDatabaseOperations(object):

    """

django/db/backends/mysql/base.py

+1 −0
Original line number Diff line number Diff line
@@ -110,6 +110,7 @@ class CursorWrapper(object): 
class DatabaseFeatures(BaseDatabaseFeatures):

    empty_fetchmany_value = ()

    update_can_self_select = False

    related_fields_match_type = True



class DatabaseOperations(BaseDatabaseOperations):

    def date_extract_sql(self, lookup_type, field_name):

django/db/models/fields/related.py

+7 −2
Original line number Diff line number Diff line
@@ -695,8 +695,13 @@ class ForeignKey(RelatedField, Field): 
        # of the field to which it points. An exception is if the ForeignKey

        # points to an AutoField/PositiveIntegerField/PositiveSmallIntegerField,

        # in which case the column type is simply that of an IntegerField.

        # If the database needs similar types for key fields however, the only

        # thing we can do is making AutoField an IntegerField.

        rel_field = self.rel.get_related_field()

        if isinstance(rel_field, (AutoField, PositiveIntegerField, PositiveSmallIntegerField)):

        if (isinstance(rel_field, AutoField) or

                (not connection.features.related_fields_match_type and

                isinstance(rel_field, (PositiveIntegerField,

                                       PositiveSmallIntegerField)))):

            return IntegerField().db_type()

        return rel_field.db_type()

tests/regressiontests/model_regress/models.py

+23 −0
Original line number Diff line number Diff line
@@ -32,6 +32,20 @@ class Party(models.Model): 
class Event(models.Model):

    when = models.DateTimeField()



class Department(models.Model):

    id = models.PositiveIntegerField(primary_key=True)

    name = models.CharField(max_length=200)



    def __unicode__(self):

        return self.name



class Worker(models.Model):

    department = models.ForeignKey(Department)

    name = models.CharField(max_length=200)



    def __unicode__(self):

        return self.name



__test__ = {'API_TESTS': """

(NOTE: Part of the regression test here is merely parsing the model

declaration. The verbose_name, in particular, did not always work.)
@@ -95,5 +109,14 @@ u'' 
datetime.datetime(2000, 1, 1, 13, 1, 1)

>>> e.get_previous_by_when().when

datetime.datetime(2000, 1, 1, 6, 1, 1)



# Check Department and Worker

>>> d = Department(id=10, name='IT')

>>> d.save()

>>> w = Worker(department=d, name='Full-time')

>>> w.save()

>>> w

<Worker: Full-time>



"""

}