学校的一个教务处管理系统，包括学生信息、教师信息、班级信息等-Office of Academic Affairs of a school management system, including student information, teacher information, class information, etc.

PHP s database access functions are not standardised. This creates a need for a database class library to hide the differences between the different database API s (encapsulate the differences) so we can easily switch databases. PHP 4.0.5 or later is