I have been writing software for a while but until now have managed to avoid almost any connection with sql and now I think I have a sql problem. I have written and released a FOSS Campground Reservation System () and I am having a problem with a new feature I want to incorporate. In the system I have a reservations table which refers to a spaces table which refers to a price table which contains the rates (daily, weekly etc.) which vary depending on the features of the spaces. When I want a rate associated with a space I can simply do @space.price.daily_rate and there we have it. Simple. Now I have a request to change the system so that I can have differing rates for different times like winter rates and summer rates and holiday rates etc. The tables currently look like this (many details omitted): create_table “reservations”, :force => true do |t| t.column “space_id”, :integer, :default => 0, :null => false # … (a lot of unrelated details of the reservation) end create_table “spaces”, :force => true do |t| t.column “name”, :string, :limit => 24, :default => “”, :null => false # each space may refer to a different price or many may refer to a single price t.column “price_id”, :integer, :limit => 3, :default => 0, :null => false # … (a lot of unrelated details of the space like size and equipment) end create_table “prices”, :force => true do |t| # name is for administrative convenience only t.column “name”, :string, :limit => 24, :default => “”, :null => false t.column “daily_rate”, :integer, :limit => 5, :default => 0, :null => false t.column “weekly_rate”, :integer, :limit => 5, :default => 0, :null => false t.column “monthly_rate”, :integer, :limit => 6, :default => 0, :null => false end I have come up with a season table which includes the start and end dates and a name along with a method that returns the season for a reservation given the dates. I am trying to understand how I can shoehorn this concept into my system. I want to be able to, in a simple manner, retrieve the rate applicable to a given space during a given season. I know I will have to modify the prices in some manner to identify the association of price to season but how do I tie it all together? Thanks for any help Norm