Cml\Db\MySql\Pdo::truncate PHP Method

    public function truncate($tableName)
    {
        $tableName = $this->tablePrefix . $tableName;
        $stmt = $this->prepare("TRUNCATE {$tableName}");
        $this->setCacheVer($tableName);
        return $stmt->execute();
        //不存在会报错，但无关紧要
    }