Errors in file /u01/app/oracle/diag/rdbms/testadg/testadg/trace/testadg_mrp0_70058.trc:
ORA-01111: name for data file 294 is unknown - rename to correct file
ORA-01110: data file 294: '/u01/app/oracle/product/12.2.0/dbhome_1/dbs/UNNAMED00294'
ORA-01157: cannot identify/lock data file 294 - see DBWR trace file
ORA-01111: name for data file 294 is unknown - rename to correct file
ORA-01110: data file 294: '/u01/app/oracle/product/12.2.0/dbhome_1/dbs/UNNAMED00294'
2020-02-10T10:00:11.075577+08:00
MRP0: Background Media Recovery process shutdown (testadg)
2020-02-10T10:09:30.495418+08:00
Errors in file /u01/app/oracle/diag/rdbms/testadg/testadg/trace/testadg_m000_70303.trc:
ORA-01110: data file 294: '/u01/app/oracle/product/12.2.0/dbhome_1/dbs/UNNAMED00294'
ORA-01565: error in identifying file '/u01/app/oracle/product/12.2.0/dbhome_1/dbs/UNNAMED00294'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 7
上面的问题是由于在主库添加数据文件，adg备库不知道数据文件的创建路径导致的。永久解决该问题可以执行：
alter system set db_create_file_dest='数据文件路径' scope=spfile;
针对ORA-01111 ORA-01110 ORA-01157错误解决方案
1）取消日志应用
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
2）修改standby_file管理方式为手工
ALTER SYSTEM SET STANDBY_FILE_MANAGEMENT=MANUAL; （单节点）
ALTER SYSTEM SET STANDBY_FILE_MANAGEMENT=MANUAL SID='*'; （RAC）
3）重命名未知的294号文件
ALTER DATABASE RENAME FILE '/u01/app/oracle/product/12.2.0/dbhome_1/dbs/UNNAMED00294' to '/oradata/testadg/8d3b923bd0d2f7e5e053110b08bc5629/datafile/ts_data_data.338.1031997447';
或者
Alter database create datafile '/u01/app/oracle/product/12.2.0/dbhome_1/dbs/UNNAMED00294' as '/oradata/testadg/8d3b923bd0d2f7e5e053110b08bc5629/datafile/ts_data_data.338.1031997447' ;
4）修改standby_file管理方式为自动
ALTER SYSTEM SET STANDBY_FILE_MANAGEMENT=AUTO;
ALTER SYSTEM SET STANDBY_FILE_MANAGEMENT=AUTO SID='*'; ###rac
5）开启日志事实应用
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT;
