To reset the recovery catalog to an older incarnation:

   1. Specify the primary key of the desired database incarnation. Obtain the incarnation key value by issuing a LIST command:

LIST INCARNATION;

List of Database Incarnations
DB Key  Inc Key   DB Name   DB ID       CUR    Reset SCN    Reset Time
------- -------   -------   ------      ---    ----------   ----------
1       2         TRGT      1224038686  NO     1            02-JUL-01
1       582       TRGT      1224038686  YES    59727        10-JUL-01

   2. Reset the database to the old incarnation. For example, enter:

RESET DATABASE TO INCARNATION 2;

   3. Shut down the database and start it without mounting. For example:

SHUTDOWN IMMEDIATE
STARTUP NOMOUNT

   4. Restore a control file from the old incarnation.
 If you have a control file tagged, then specify the 
tag. Otherwise, you can run the SET UNTIL command, as 
in this example:

RUN 
{
  SET UNTIL 'SYSDATE-45';
  RESTORE CONTROLFILE;
}

   5. Mount the restored control file:

ALTER DATABASE MOUNT;

   6. Run RESTORE and RECOVER commands to restore and 
recover the database files from the prior incarnation, 
then open the database with the RESETLOGS option. For 
example, enter:

RESTORE DATABASE;
RECOVER DATABASE;
ALTER DATABASE OPEN RESETLOGS;