That is pretty close to how it would look using happstack-state. Here is a complete, runnable example which defines the types, a query, creates/initializes the database, performs the query, and prints the results. [snip]
How is data stored in Happstack.State? I see the "Component" instance uses "fromList" from happstack-ixset but can't find any information on the algorithm used or its efficiency (computationally or wrt space). If making this more concrete helps then here is a possible use: == GPS Points == I have a GPS logger that logs every 10 seconds when I jog. Jogging for an hour a day for the past 180 days has resulted in 64k points. Pretending I hosted a site for joggers (and all points were in the same DB) I could easily result in a billion points (< 20K users). Would happstack-ixset code in the form "points @< (Lon -120) @> (Lon -125) @> (Lat 45) @< (Lat 50)" perform reasonably? Cheers, Thomas