PDO使用特定于数据库的 pdo_mysql手册页上，有一些有关安装驱动程序的详细信息. ，或者可能有一个可以使用的BSD软件包(恐怕我对BSD不够熟悉，无法提供具体建议).

PDO uses database specific drivers to connect to database systems. It looks like you are missing the pdo_mysql driver that is required to connect to a MySQL database. There is some details on installing the driver on the pdo_mysql manual page, or there may be a BSD package that you can use (I am afraid I'm not familiar enough with BSD to offer specific advice).