ORA-10459: cannot start media recovery on standby database; conflicting state detected
Cause: An attempt was made to perform media recovery on a standby database while another instance was performing recovery on the standby database, had the standby database open, or a data file move operation was in progress.
Action: Close the standby on all other instances, cancel any conflicting recovery session or data file move operation, and perform manual recovery.
ORA-10459错误指示无法在备份数据库中开始媒体恢复，原因是检测到了冲突状态。 这是由于在同一时刻活动数据库和备份数据库中的状态不一致造成的，其中一个或两个数据库的时钟可能不同步。
ORA-10459: cannot start media recovery on standby database; conflicting state detected
Cause: Media recovery was requested on a standby database, but the supplied RBA and host name indicated a conflicting state.
Action: Check the standby database as to its readiness to begin media recovery and that host name and RBA are in sync with the primary database.
这个错误通常发生在尝试在活动数据库上开始媒体恢复时，因为主要数据库和备份数据库的运行状态（时钟和SCN）不匹配而发生冲突。
1.用show parameter name检查时钟，看看能否再次同步。
2.检查系统快照比（SSB）来确定是否有冲突。
3.从Controlfile和Redo log中查看备份数据库是否准备就绪，可以运行媒体恢复。
4.试图用RMAN重建控制文件，重新生成备份数据库，以使其准备好进行媒体恢复。
5.最后，如果仍然无法解决问题，可以尝试从备份文件中立即恢复数据库。