@zvoni: It you want to this, you better use a 'classical' collection :-) To transfer the data from the RS to a classical construct to deal with.
Working with a Serverbased DB is working with unknown amount of data. And a count of a DB is only valid for the time of asking. With a local sqlite it will be ok, but in a multiuser enviroment the answer can be false in the next moment, because the data in the table can be changed in the meanwhile.
@nugax: If you are using the DB singleuser/process you can do a firts/last and read the the data as zvoni mententions (IMHO the data will be buffered an if you itertate it is also fetched from internal caches - test it - depending on you data you will see nearly no delay - at sqilte local), but the best way is, to think about the design to avoid this fixed constructs.