One good feature flashback of oracle 10g

1. use database as archive log mode and set archive dest location
alter system set LOG_ARCHIVE_DEST_1 = 'LOCATION=/u04/arch/orcl' scope=spfile;
2. configuration retention days/size/distination
ALTER SYSTEM SET DB_FLASHBACK_RETENTION_TARGET=43200; --30 days
ALTER SYSTEM SET db_recovery_file_dest_size=10g SCOPE=BOTH;
ALTER SYSTEM SET db_recovery_file_dest='/u04/flash_recovery_area/orcl' SCOPE=BOTH;
3. enalbe database flashback
ALTER DATABASE FLASHBACK ON;
4. create restore pint
CREATE RESTORE POINT before_upgrade GUARANTEE FLASHBACK DATABASE;
SELECT NAME, SCN, TIME, DATABASE_INCARNATION#,GUARANTEE_FLASHBACK_DATABASE,STORAGE_SIZE from V$RESTORE_POINT;
DROP RESTORE POINT BEFORE_UPGRADE;
5. do some changes.
6. rollback database to restore point
SHUTDOWN IMMEDIATE;
STARTUP MOUNT;
FLASHBACK DATABASE TO RESTORE POINT 'BEFORE_UPGRADE';
ALTER DATABASE OPEN RESETLOGS;
7. Clear space for flashback database
You can disable Flashback Database with the ALTER DATABASE FLASHBACK OFF command.
As a consequence, all existing Flashback Database logs are deleted automatically.