Some Times you need to Restore your Database To Earlier time , and before doing that you have to check weather database have valid to do that or not
Simple Query :
SQL> select resetlogs_change#,to_char(resetlogs_time,
'DD-MON-YYYY HH24:MI:SS') Last_resetlog_time from v$database_incarnation;
RESETLOGS_CHANGE# LAST_RESETLOG_TIME
----------------- --------------------
1 11-SEP-2008 22:57:51
88033 23-MAY-2011 10:12:42
Or Sometimes you could Usev$restore_point , Such as
SELECT scn, time, database_incarnation#, guarantee_flashback_database from
v$restore_point;
Thank you
Osama Mustafa