diff options
Diffstat (limited to 'django/db')
| -rw-r--r-- | django/db/models/options.py | 15 | ||||
| -rw-r--r-- | django/db/models/sql/query.py | 8 |
2 files changed, 19 insertions, 4 deletions
diff --git a/django/db/models/options.py b/django/db/models/options.py index 5d8a7b7104..292de67910 100644 --- a/django/db/models/options.py +++ b/django/db/models/options.py @@ -436,6 +436,21 @@ class Options(object): result.update(parent._meta.get_parent_list()) return result + def get_ancestor_link(self, ancestor): + """ + Returns the field on the current model which points to the given + "ancestor". This is possible an indirect link (a pointer to a parent + model, which points, eventually, to the ancestor). Used when + constructing table joins for model inheritance. + + Returns None if the model isn't an ancestor of this one. + """ + if ancestor in self.parents: + return self.parents[ancestor] + for parent in self.parents: + if parent._meta.get_ancestor_link(ancestor): + return self.parents[parent] + def get_ordered_objects(self): "Returns a list of Options objects that are ordered with respect to this object." if not hasattr(self, '_ordered_objects'): diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py index c8c25bd711..550e6e323c 100644 --- a/django/db/models/sql/query.py +++ b/django/db/models/sql/query.py @@ -494,14 +494,14 @@ class BaseQuery(object): aliases = set() if start_alias: seen = {None: start_alias} - root_pk = opts.pk.column for field, model in opts.get_fields_with_model(): if start_alias: try: alias = seen[model] except KeyError: + link_field = opts.get_ancestor_link(model) alias = self.join((start_alias, model._meta.db_table, - root_pk, model._meta.pk.column)) + link_field.column, model._meta.pk.column)) seen[model] = alias else: # If we're starting from the base model of the queryset, the @@ -1005,13 +1005,13 @@ class BaseQuery(object): as_sql()). """ opts = self.model._meta - root_pk = opts.pk.column root_alias = self.tables[0] seen = {None: root_alias} for field, model in opts.get_fields_with_model(): if model not in seen: + link_field = opts.get_ancestor_link(model) seen[model] = self.join((root_alias, model._meta.db_table, - root_pk, model._meta.pk.column)) + link_field.column, model._meta.pk.column)) self.included_inherited_models = seen def remove_inherited_models(self): |