Dynamically compute geometry for reference track

[lewismc]

At today's tagup, Jesus presented a use case which dynamically computes the geometry for a reference track

UPDATE data_position SET the_geom = st_setsrid(st_makepoint(cast(data_position.lon as float), cast(data_position.lat as float)), 4326);

ALTER TABLE data_position ADD COLUMN the_geom geometry(Point,4326);

We DO NOT want to include this in the data model but we could possibly include a stored procedure which could be triggered on-demand.