Returns the # of flowers per property per garden. Columns:
o property (name)
o garden (name)
o garden_id
o count

select p.name as property, g.name as garden, fl.garden_id, count(*) from properties p, gardens g, flower_locations fl where fl.garden_id = g.id and g.property_id = p.id group by p.name, g.name, fl.garden_id