ORA-01157: cannot identify/lock data file 4 – see DBWR trace file
ORA-01110: data file 5: ‘D:\ORACLE11204\ORADATA\PEGA\EXAMPLE01.DBF’
Error occurred due to DBWR process not able to lock the file for its use during startup of database.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01157: cannot identify/lock data file 5 - see DBWR trace file
ORA-01110: data file 5: 'D:\ORACLE11204\ORADATA\PEGA\EXAMPLE01.DBF'
Solution
So, We need to check which process caused lock on the datafiles. if we did not found it may be corrupted we need to restore from backup. We can also use the RMAN Advisory: Example of RMAN Advisory
SQL> alter database datafile 5 offline;
Database altered.
SQL> alter database open;
Database altered.
Recover and restore the datafile 5 though rman process:
RMAN> restore datafile 5;
Starting restore at 04-FEB-16
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=133 device type=DISK
channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00005 to D:\ORACLE11204\ORADATA\PEGA\EXAMPLE01.DBF
channel ORA_DISK_1: reading from backup piece D:\BACKUP\FULL_DB_902883257_681P1
channel ORA_DISK_1: piece handle=D:\BACKUP\FULL_DB_902883257_681P1 tag=TAG20160204T005417
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:25
Finished restore at 04-FEB-16
RMAN> recover datafile 5;
Starting recover at 04-FEB-16
using channel ORA_DISK_1
starting media recovery
media recovery complete, elapsed time: 00:00:01
Finished recover at 04-FEB-16
Open the datafile in read and write mode.
RMAN> sql "alter database datafile 5 online";
sql statement: alter database datafile 5 online
Note: If you have downtime then do once clean shutdown and startup database
Take fresh backup of database after datafile 5 online.
