You will probably want to use OFFSET and LIMIT, which are the window size and page. Something like
SELECT .. FROM ... WHERE ... ORDER BY (...) OFFSET y LIMIT x
So say you want to get 100 records at a time. You would get page 1 with OFFSET 0 LIMIT 100, then page 2 with OFFSET 100, OFFSET 200, and so on.
That's just off the top of my head. There may be another solution which will work better in your case, but lacking details, this is what I would recommend.