Simulated recover Oracle restoration test for accidental deletion of dataifle 1: 1. hot Backup tablespace users. 2. a) scott login, B) create table tt (seq number); c) declare I number; begin for I in 1 .. 20 loop insert into tt values (I); end loop; commit; end; d) alter system switch logfile; e) insert into tt values (21 ); alter system switch logfile ;... until all online redo files have archived (Application for testing the archived log) f) commit; 3. shutdown immediate; 4. rm datafile users; recovery: SQL> startup ORACLE instance started. total System Global Area 285212672 bytes Fixed Size 1218992 bytes Variable Size 121636432 bytes Database Buffers 159383552 bytes Redo Buffers 2973696 bytes Database mounted. ORA-01157: cannot identify/lock data file 4-see DBWR trace file ORA-01110: data file 4: '/oracle/product/10.2.0/oradata/orcl/users01.dbf' SQL> host cp/oracle/backup/users01.dbf/oracle/product/10.2.0/oradata/orcl/SQL> alter database open; alter database open * ERROR at line 1: ORA-01113: file 4 needs media recovery ORA-01110: data file 4: '/oracle/product/10.2.0/oradata/orcl/users01.dbf' SQL> recover tablespace users; ORA-00279: change 546700 generated at 05/14/2013 20:51:07 needed for thread 1 ORA-00289: suggestion: /oracle/product/10.2.0/db_1/flash_recovery_area/ORCL/archivelog/2013_05_14/o1_mf_1_6 _ % u _. arc ORA-00280: change 546700 for thread 1 is in sequence #6 --- ORA-00289: Lookup archived log file recovery... because Specify log: {<RET> = suggested | filename | AUTO | CANCEL} Log applied. media recovery complete. SQL> alter database open; Database altered. note: view the scn: 1. select file #, checkpoint_change # from v $ datafile_header; 2. select file #, checkpoint_change # from v $ datafile; v $ datafile_header information comes from the file header of each data file. v $ datafile information comes from control file 3. select sequence #, first_change #, next_change # from v $ archived_log; 4. select dbms_flashback.get_system_change_number from dual; -- system scn