Oralce Recovery in non-archive mode (ii) log is switched and history log is overwritten

Case 2: The log is switched and the history log is overwritten (only incomplete recovery is possible)

1) Simulation Environment

sql> INSERT into SCOTT.TB01 values (777);

1 row created.

sql> INSERT INTO SCOTT.TB01 values (888);

1 row created.

Sql> commit;

Commit complete.

Sql> col status for A10

Sql> select * from V$log;

group# thread# sequence# BYTES members archived STATUS first_change#

---------- ---------- ---------- ---------- ---------- --------- ---------- ------------- -------------------

1 1 104857600 3 NO INACTIVE 845923 2012-03-22 14:53:47

4 1 8 104857600 3 YES INACTIVE 801096 2012-03-21 18:22:29

3 1 9 104857600 3 YES INACTIVE 821972 2012-03-22 11:42:07

2 1 104857600 3 NO current 866474 2012-03-22 15:22:09

sql> alter system switch logfile;

System altered.

sql> alter system switch logfile;

System altered.

sql> alter system switch logfile;

System altered.

sql> alter system switch logfile;

System altered.

Sql> select * from V$log;

group# thread# sequence# BYTES members archived STATUS first_change#

---------- ---------- ---------- ---------- ---------- --------- ---------- ------------- -------------------

1 1 104857600 3 NO INACTIVE 866795 2012-03-22 15:25:45

4 1 104857600 3 NO current 866803 2012-03-22 15:26:04

3 1 104857600 3 NO INACTIVE 866787 2012-03-22 15:25:25

2 1 104857600 3 NO INACTIVE 866798 2012-03-22 15:25:53

Sql> select * from SCOTT.TB01;

Id

----------

444

555

666

888

111

222

333

777

8 rows selected. --The log has been overwritten

sql> Shutdown Abort

ORACLE instance shut down.

Sql>!

[ORACLE@SOLARIS10 ~] $rm/u01/app/oracle/oradata/anny/test*.dbf

2) Start the database

Sql> Startup

ORACLE instance started.

Total System Global area 314572800 bytes

Fixed Size 1279964 bytes

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