Flashback, what did this data look like previously?
I'm only scratching the surface of what you can do with flashbacks in Oracle. Our DBAs are absolute ninjas when it comes to using this witchcraft from Oracle.
The example below lets us look at a data dictionary for materialized refresh groups and what the values were an hour ago.
CLEAR SCREEN COL name FORMAT a30 COL rname FORMAT a30 SELECT name, rname FROM all_refresh_children AS OF TIMESTAMP ( trunc(SYSDATE - 1 / 24) ) WHERE rname = 'RFG_GROUP2';
1 / 24is an hour ago
36 / 24is yesterday an hour and half ago