convert scn numbers

The scn number is very important. Whenever a change to the database is made (including the data dictionary) then this scn number is incremented. Oracle uses the scn number for backup / recovery purposes, flashback, recycle bin etc etc etc.

There are a few functions that can be used to convert scn numbers to dates and vice a versa, which may make life easier when working out what date these scn numbers refer to. These functions must look through control file as they will fail if the scn number is too old.

select dbms_flashback.get_system_change_number from dual;
select current_scn from v$database;

select scn_to_timestamp(to_char(timestamp_to_scn(sysdate),'99999999999')) from dual;
select to_char(timestamp_to_scn(sysdate),'99999999999') from dual

note:
These queries will convert the scn number to a timestamp and vice a versa.