Ticket #14691: multidb_foreignkey_validation_patch.diff

django/db/models/fields/related.py

@@ -834 +834 @@
         super(ForeignKey, self).validate(value, model_instance)
         if value is None:
             return
-
-        qs = self.rel.to._default_manager.filter(**{self.rel.field_name:value})
+        
+        using = router.db_for_read(model_instance.__class__, instance=model_instance)
+        qs = self.rel.to._default_manager.using(using).filter(**{self.rel.field_name:value})
         qs = qs.complex_filter(self.rel.limit_choices_to)
         if not qs.exists():
             raise exceptions.ValidationError(self.error_messages['invalid'] % {