1. Sample Problem: Log Of Failures 问题样例：故障记录 当INSERT失败时，我希望能将其记录在日志文件中我们用来展示出错处理的问题样例是很 普通的。我希望得到错误的记录。当INSERT失败时，我想在另一个文件中记下这些错误的 信息，例如出错时间，出错原因等。

Sequences in MySQL help ensure that values aren't repeated, and many applications require database tables to have an incrementing "id" column. The MySQL syntax offers several ways to avoid repeating ...