先来解释下什么是错误缓冲区？在MySQL里面，错误缓冲区只记录最近一次出现的错误，只要是有新的错误产生，旧的就会被覆盖掉。所以想知道产生了什么错误，就得在
先来解释下什么是错误缓冲区？
在MySQL里面， 错误缓冲区只记录最近一次出现的错误， 只要是有新的错误产生，旧的就会被覆盖掉。 所以想知道产生了什么错误，
就得在每个有可能发生错误的语句后面紧跟着"show warnings" 或者 "show errors"。 最简单的方法是把输出的结果重定向到自己定义的
日志文件里面，这样就可以方便后续查看。当然如果想随时查看这些错误，我们就得通过MySQL提供的API来实现。
自从MySQL 5.6 这个革命性的版本出现后，问题得到了初步解决。虽然离我们想的还差好多。
MySQL 5.6 提供了 get diagnostic 语句来获取错误缓冲区的内容，然后把这些内容输出到不同范围域的变量里，以便我们后续灵活操作。
下来，我们就来看一个例子。
针对的表结构为：
存储过程代码为：
我们来执行上面的存储过程，服务器空间，完了后，网站空间，就能把错误信息保存到SESSION 变量@i_result 中。这样，香港空间，方便了后期进行各种输出。
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