protected function generateUpdateSQL(Update $update)
        {
            $updates = [];
            foreach ($update->getValues() as $column => $value) {
                $column = mb_substr($column, mb_strpos($column, '.') + 1);
                $prefix = Query::quoteIdentifier($column);
                $updates[] = $prefix . Criterion::EQUALS . '?';

                $this->addValue($value, true);
            }
            $sql = 'UPDATE ' . $this->getTable()->getSqlTableName() . ' SET ' . implode(', ', $updates);
            return $sql;
        }