mysql错误处理_MySQL
1、数据库服务器断开连接后，客户端大量执行（我的问题出现随4000次左右query出现）query，造成MySQL client ran out of memory。
mysql的连接会偶发性的断掉，所以每次mysql_query()之前应该检查是否在连接状态（如何检查？，没发现有直接使用的api）。或执行query之后检查mysql_errno()，如果为CR_SERVER_GONE_ERROR或CR_SERVER_LOST，则需要重连。
如果已经断开了连接，再进行大量的mysql_query(),会造成新连接出现MySQL client ran out of memory错误。这样会造成后续的重新连接也无法成功。
简单解决方法：
每次query失败检查错误码，如果为CR_SERVER_GONE_ERROR或CR_SERVER_LOST，则做一次重连再试。
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