protected function getIgnore()
    {
        if (!empty($this->config['tables'])) {
            return '';
        }
        $ignoreTables = array_merge($this->config['structureTables'], $this->config['ignoreTables']);
        // Append the ignore-table options.
        $ignoreArgs = [];
        foreach ($ignoreTables as $table) {
            $ignoreArgs[] = escapeshellarg($this->config['database'] . '.' . $table);
        }
        array_unshift($ignoreArgs, str_repeat(' --ignore-table=%s', count($ignoreArgs)));
        return trim(call_user_func_array('sprintf', $ignoreArgs));
    }