I know that "belongs_to :through" is not valid. It's just my attempt to express what I want to achieve. Just bear with me for a sec...
This is what I have:
class League
has_many :divisions
end
class Division
belongs_to :league
has_many :teams
end
class Team
belongs_to :division
has_many :players
end
class Player
belongs_to :team
end
Now, in order to make a "baseball card" view form, I need:
name
team.name
team.division.name
team.division.league.name
So, is there a way to set up a "belongs_to :through" association to directly access 'division.name' from 'players_controller' without the 'team.' prefix?? I have to access a lot of columns from 'player' to 'division', so I'm looking for a way to get "direct" access to those columns.
One option is to include a 'division_id' column in the 'players' table, but I've been told that it would kinda break the relational data model, since it would allow for inconsistency if the data selection functionality is not properly handled (eg player A is on team A which is in division A, but player A has its division_id column set to division B).
Is it possible to make a "symbolic link", eg 'division' now refers to 'team.division', and 'league' now refers to 'team.division.league'??
Or, is the only true option to use the full path each time??
Hope someone can help.
Use delegate in the model class.
class Team < ActiveRecord::Base
belongs_to :division
has_many :players
delegate :league, to: :division
end
Reference: http://api.rubyonrails.org/classes/Module.html#method-i-delegate
You may try
class Player belongs_to :team has_one :division, :through => :team end
You can define a helper method in your player model:
def division
team.division
end
def league
team.division.league
end
Of course, this only relates to readability of your code and does not affect the form of the database queries involved. If your statement generates multiple SQL queries but you want only one, check out the .include
option here: Rails Guides - Active Record Query Interface
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