思路分析: 1.发现数据库宕机,检查alert日志发现如下出现控制文件:I/O错误 Thu Apr 11 06:40:14 2019WARNING: Read Failed. group:2 disk:1 AU:675 offset:16384 size:16384WARNING: failed to read mirror side 1 of virtual extent 0 logical extent 0 of file 260 in group [2.3852408873] from d