Ticket #5309: base.py.2.diff

django/django/db/models/base.py

@@ -98 +98 @@
         return not self.__eq__(other)
 
     def __init__(self, *args, **kwargs):
+        # We use this to keep track if the row has already been saved in the db.
+        self._is_stored = None
         dispatcher.send(signal=signals.pre_init, sender=self.__class__, args=args, kwargs=kwargs)
 
         # There is a rather weird disparity here; if kwargs, it's set, then args
@@ -214 +216 @@
         # Note: the comparison with '' is required for compatibility with
         # oldforms-style model creation.
         pk_set = pk_val is not None and pk_val != u''
-        record_exists = True
-        if pk_set:
+        record_exists = False
+        if self._is_stored is not False:
             # Determine whether a record with the primary key already exists.
             cursor.execute("SELECT 1 FROM %s WHERE %s=%%s" % \
                 (qn(self._meta.db_table), qn(self._meta.pk.column)),
@@ -229 +231 @@
                         ','.join(['%s=%%s' % qn(f.column) for f in non_pks]),
                         qn(self._meta.pk.column)),
                         db_values + self._meta.pk.get_db_prep_lookup('exact', pk_val))
-            else:
-                record_exists = False
-        if not pk_set or not record_exists:
+                    record_exists = True
+        if not record_exists:
             field_names = [qn(f.column) for f in self._meta.fields if not isinstance(f, AutoField)]
             db_values = [f.get_db_prep_save(raw and getattr(self, f.attname) or f.pre_save(self, True)) for f in self._meta.fields if not isinstance(f, AutoField)]
             # If the PK has been manually set, respect that.
@@ -256 +257 @@
                      connection.ops.pk_default_value()))
             if self._meta.has_auto_field and not pk_set:
                 setattr(self, self._meta.pk.attname, connection.ops.last_insert_id(cursor, self._meta.db_table, self._meta.pk.column))
+            self._is_stored = True
         transaction.commit_unless_managed()
 
         # Run any post-save hooks.