As part of our backup/recovery process we don a RMAN backup along with
a full export of a 4.5TB database. To limit what is pumped out I would
like to limit my export to only those tables/partitons, which have changed
for the current day or maybe the day before.

By change, I mean any inserts,updates or deletes.....

Does anybody know of such a query that will give me this information,
which I can use to dynamically build a parfile through a shell script than
invoke expdp.

Any examples would be greatly appreciated.

Thanks to all who answer.