Sequential Select fromDB

Hi Experts,

I have a DB with more than 30 million records.

I would like to process the records using the packet size <p_pckt>.

My Requirement is :

I would read the first <p_pckt> records first from the DB.

Then later on when I come to execute the report some other day i would start and processing from <p_pckt> + 1 record in the DB and so on.

Could any one suggest some efficient way of doing it.

Regards

Sandeep