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由于在9月30号粗暴地打断了一个导入进程，今天发现MySQL竟然不能启动了，只好卸载重装（也许可以花些时间查找问题，但是这个来的更快些）。重启导入进程，却出现了数据库已存在的提示信息。于是就进入命令行窗口drop database myapp，可是却得到了ERROR 1010 (HY000): Error dropping database (can't rmdir './myapp', errno: 39)的错误信息。
解决方法：删除/var/lib/mysql/myapp下面的所有文件，不要删除myapp本身。然后再通过命令行drop database就可以了
摘自：mydeman的学习日志
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