[erlang-questions] sending data down the wire in mysql vs. mnesia

[Andrew Arrow]

I have a PHP + mysql app now that uses a mysql stored procedure to
avoid sending lots of data "down the wire."  That is, the stored
procedure iterates over thousands of rows, determines the value the
app needs and sends back just the value.  This avoids the thousands of
rows coming down the wire to have PHP compute the value.

In moving this system to erlang + mnesia do I have to worry about the
same issue?  It seems I will have to store the thousands of items in a
set in a mnesia table, retrieve all the rows, and have erlang compute
the value.  There's no way to do the iteration inside mnesia like
there is in mysql is there?