TabDiff is a free software to compare two Oracle tables, and report record level differences in them. It can also create an Insert, Update, and Delete SQL script to sync target Oracle table with source table.
For comparing Oracle tables with TabDiff, it is not necessary that both the tables are in same database. Also, the table names can be different, and can have different number of columns. TabDiff will just compare those columns in the tables that have same name. Even if the datatype of columns is different, they can still be compared.
If you want to exclude some column from comparison, you can do that. You can also choose to create an undo script that can undo the changes that were done by sync script.
Also Read: How to compare and sync two Oracle databases.
TabDiff is completely free software to compare Oracle tables, and is easy to use. Download it here.