Cause: The background process was either unable to find one of the data files or
failed to lock it because the file was already in use.
The database will prohibit access to this file but other files will be unaffected.
However, the first instance to open the database will need to access all online data files.
Accompanying error from the operating system describes why the file could not be identified.
Action: Have the operating system make the file available to the database.
[oracle@trichydoyen]$cd /u01/doyendb/data
[oracle@trichydoyen]$ls
system01.dbf sysaux01.dbf undotbs01.dbf users01.dbf
[oracle@trichydoyen]$mv users01.dbfusers02.dbf
[oracle@trichydoyen]$!Sq
SQL*Plus: Release 12.2.0.1.0 Production on FRI Sep 18 10:57:38 2020
Copyright (c) 1982, 2016, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 – 64bit Production
SQL>alterdatabaseopen;
alterdatabaseopen*ERRORatline1:
ORA–01157:cannotidentify/lockdatafile4–seeDBWRtracefile
ORA–01110:datafile5:’u01/data/users01.dbf’
SQL>select open_mode from v$database;
OPEN_MODE
——————–
MOUNTED
SQL>SELECT MEMBER FROM V$LOG G, V$LOGFILE F WHERE G.GROUP# = F.GROUP# AND G.STATUS = ‘CURRENT’;
MEMBER
——————————————————————————–
/u01/doyen/redo/redo01.log
SQL> RECOVER DATABASE USING BACKUP CONTROLFILE UNTIL CANCEL
ORA-00279: change 55636 generated at 07 09 2020 21:37:38 needed for thread 1
ORA-00289: suggestion :/u01/app/oracle/product/12.2.0.1/db_1/dbs/arcr_1_111.arc
ORA-00280: change 55636 for thread 1 is in sequence #111
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
/u01/doyendb/redo/redo01.log
Log applied.
Media recovery complete.
SQL>alter database open resetlogs;
Database altered.
SQL>select open_mode from v$database;
OPEN_MODE
——————–
READ WRITE
