Well pg's answer above tells you what sql query to run.
since you are from a programming background it should be quite easy to automate the process in perl.
Install the following modules
-DBI-1.39
-DBD-ORACLE
-DBI-Shell-11.93 (optional).
Once you have these you can write a perl script to connect to the database and run the query given by PG.
If you are interested ,programming the perl DBI is a book that explains how to to this.
SQL "-" is the most appropriate way,though another one can be writing the output of select * from table to a file and using the diff utility.
HTH
<update :as you can see roger beat me to it :)>

In reply to Re: need to look for data differences in same table in two database instances by chimni
in thread need to look for data differences in same table in two database instances by Anonymous Monk

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