def _delete_null_columns(self): """ executes a delete query to remove columns that have changed to null """ ds = DeleteStatement(self.column_family_name, if_exists=self._if_exists) deleted_fields = False for _, v in self.instance._values.items(): col = v.column if v.deleted: ds.add_field(col.db_field_name) deleted_fields = True elif isinstance(col, columns.Map): uc = MapDeleteClause(col.db_field_name, v.value, v.previous_value) if uc.get_context_size() > 0: ds.add_field(uc) deleted_fields = True if deleted_fields: for name, col in self.model._primary_keys.items(): ds.add_where_clause(WhereClause( col.db_field_name, EqualsOperator(), col.to_database(getattr(self.instance, name)) )) self._execute(ds)
def _delete_null_columns(self): """ executes a delete query to remove columns that have changed to null """ ds = DeleteStatement(self.column_family_name) deleted_fields = False for _, v in self.instance._values.items(): col = v.column if v.deleted: ds.add_field(col.db_field_name) deleted_fields = True elif isinstance(col, columns.Map): uc = MapDeleteClause(col.db_field_name, v.value, v.previous_value) if uc.get_context_size() > 0: ds.add_field(uc) deleted_fields = True if deleted_fields: for name, col in self.model._primary_keys.items(): ds.add_where_clause(WhereClause( col.db_field_name, EqualsOperator(), col.to_database(getattr(self.instance, name)) )) self._execute(ds)
def test_context_update(self): ds = DeleteStatement('table', None) ds.add_field(MapDeleteClause('d', {1: 2}, {1: 2, 3: 4})) ds.add_where_clause(WhereClause('a', EqualsOperator(), 'b')) ds.update_context_id(7) self.assertEqual(six.text_type(ds), 'DELETE "d"[%(8)s] FROM table WHERE "a" = %(7)s') self.assertEqual(ds.get_context(), {'7': 'b', '8': 3})