From 99321e30cebbffeafc6ae19f4f92a0a665cbf19b Mon Sep 17 00:00:00 2001 From: Andrei Antoukh Date: Sun, 12 Aug 2012 22:17:54 +0300 Subject: Fixed #18306 -- Made deferred models issue update_fields on save Deferred models now automatically update only the fields which are loaded from the db (with .only() or .defer()). In addition, any field set manually after the load is updated on save. --- django/db/models/base.py | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'django') diff --git a/django/db/models/base.py b/django/db/models/base.py index 30e07be3a7..1e1a138714 100644 --- a/django/db/models/base.py +++ b/django/db/models/base.py @@ -475,6 +475,7 @@ class Model(six.with_metaclass(ModelBase, object)): that the "save" must be an SQL insert or update (or equivalent for non-SQL backends), respectively. Normally, they should not be set. """ + using = using or router.db_for_write(self.__class__, instance=self) if force_insert and (force_update or update_fields): raise ValueError("Cannot force both insert and updating in model saving.") @@ -502,6 +503,23 @@ class Model(six.with_metaclass(ModelBase, object)): "model or are m2m fields: %s" % ', '.join(non_model_fields)) + # If saving to the same database, and this model is deferred, then + # automatically do a "update_fields" save on the loaded fields. + elif not force_insert and self._deferred and using == self._state.db: + field_names = set() + for field in self._meta.fields: + if not field.primary_key and not hasattr(field, 'through'): + field_names.add(field.attname) + deferred_fields = [ + f.attname for f in self._meta.fields + if f.attname not in self.__dict__ + and isinstance(self.__class__.__dict__[f.attname], + DeferredAttribute)] + + loaded_fields = field_names.difference(deferred_fields) + if loaded_fields: + update_fields = frozenset(loaded_fields) + self.save_base(using=using, force_insert=force_insert, force_update=force_update, update_fields=update_fields) save.alters_data = True -- cgit v1.3