core/Mysql.php
public function existsTable(string $tbname)
    {
        $tbname = str_replace('@pf_', $this->prefix, $tbname);
        $row = $this->getRow('SHOW TABLES LIKE ?;', $tbname);
        return $row != null;
    }
public function existsTable(string $tbname)
    {
        $tbname = str_replace('@pf_', $this->prefix, $tbname);
        $row = $this->getRow('SHOW TABLES LIKE ?;', $tbname);
        return $row != null;
    }
检查表是否存在
@param string $tbname
@return bool
@throws MysqlException