Thanks, Vineet! Lot's of good info there! I don't have actual code yet, because I couldn't even get the db queries to work in a reasonable amount of time.
The little code I showed in my initial post already runs slow ( my DB records are db.itemEntry, not db.table ...). The slowness (so far) is due to doing a query/select on a very large DB. I need to figure out how to query/select more efficiently. I wonder if the problem is with sqlite3 itself, since it stores the entire DB in a single file. I have constructed index tables for the fields I am searching on, but it is still incredibly slow. (see post below in reply to Massimo too!). Thanks! Luis.