Retriving Data from Function module in update task

Hi Everyone,

My requirement is like in a report in one perform i want to select huge data (Millions of records) and then display at the end.

so i thought to do these select by using Function Module In Update Task so that it ll increase my performance.

So i created a function module of Processing type "Update module" (start immediate ) and start fetching required data from database tables.

Now i want this data (In my internal Table) back to report .

But as this is FM in Update task it will not allow for export parameters , also tables parameter will work like importing parameter.

So I tried using EXPORT/IMPORT to MEMORY ID but this is also not working .

So can you please suggest me how i can get my data in internal table back to report .

Thanks in Advance .