Also, how is the pagination api expected to work in pinot? when I ran "select * from x where foo > 3 order by foo desc limit 5, 10", it gave me all the 10 results and not starting from the offset 5

It's page 5 limit 10. If you want to return 5 records starting on page 5, it should be limit 5,5

Are you running select * in Pinot, or is that just an example? While pagination is supported in select *, it is not in aggregation