First of all, if you are using Oracle 10g, I believe to utilize data pump would be a better idea as it’s the enhanced version of the older export/import utility provided if given the source database and destination database are both Oracle 10g.
Using data pump, your entire user schema aa in source database can be basically “transported” to destination database. By that I mean, the user along with all privileges will also be created in the destination database.
The only thing you have to be concerned is whether in your source database, are profiles being set for your user schema aa. If it has, you have to create the same profile in the destination database as well prior to importing of the dump file.
The next thing would be whether identical tablespaces to host the data is a requirement during the migration of your user schema aa to the destination database. If it is a requirement, you probably have to create the same tablespaces with the same amount of storage and attributes in your destination database. If identical tablespaces are not a requirement in the destination database and you can house the imported data in current tablespaces in your destination database, data pump utility can immediately do the job.
I hope this helps. Let me know if you have problems with the command syntax. I think there’re lots of assistance on the syntax if you searched under data pump.