ORA-01274

This issue happens, when the standby_file_management parameter is set to MANUAL in standby database.

So when a datafile is added in primary database, standby database is unable to process it. To fix this issue follow the below process

1. Check the standby_file_management parameter in the standby database.

SQL> show parameter standby

2. Cancel the recovery:

SQL> recover managed standby database disconnect from session;

Media recovery complete.

3. Check the file, which caused the issue:[ STANDBY]

SQL> select file#, error, name from v$datafile_header where ERROR='FILE MISSING';

SQL> select name from v$datafile where file#=5;

SQL> alter database create datafile '/data/app/oracle/product/12c/dbhome_1/dbs/UNNAMED00005' as new;

database altered.

If you dont have OMF files, then get the exact datafile name from primary and recreate.

-- Primary

SQL> select name from v$datafile where file#=5;

-- Recreate datafile in standby

SQL> alter database create datafile '/data/app/oracle/product/12c/dbhome_1/dbs/UNNAMED00005'

as '/archive/NONPLUG/PRIM/PRIM/datafile/o1_mf_prim_d9v1fq7k_.dbf';

4. Set standby_file_management to AUTO, to avoid similar issue in future.

alter system set standby_file_management=AUTO scope=both;

5. Start recovery in standby database

alter database recover managed standby database disconnect from session;

Hope it Helps!