Is there a way I could keep track of modified tables in Oracle?
Is there a master table that keeps track of all other table's row? For example if I add a row to table1 it would update the row count stating that table1 now has 5 rows.
I was thinking of tracking either
SELECT TABLE_NAME, NUM_ROWS FROM USER_TABLES
I highly doubt you're actually using Oracle 3.1. This query works at least in 11g (I don't have other instances to test at the moment).
Keep in mind that this is a data dictionary table and it won't update automatically after you insert a row in any schema table. The Gather Statistics procedure must be run to update these records.