这些模型之间应该建立什么样的关系？

Question

I have two models: player and team.

• A player has one team

• Team has 5 fields on it (in addition to its name and location), opponent_week_1, opponent_week_2, etc.

I would like to be able to say something like Player.Team.opponent_week_1

How should I relate the models to each other? Player has_one team?

How do I set the team's opponents? I don't want the team to have_many opponents, because there will only be those 5, and I want to be able to say opponent_week_1, opponent_week_2, etc.

I am using Ruby 2 and Rails 4. Thanks!

Answer 1

jackerman09,

As with many things in Rails, there's a few ways of going about it. @phgrey pointed out how to fix the players and teams.

Regarding opponent_week_1, 2, etc.:

I think the best way is if you actually do have a has_may :opponent_week association from the Team model, like this:

class Team < ActiveRecord::Base
...
   has_many :fields
...
end

You'd then have to limit insertion of opponent weeks to each Team to only 5 through validations and/or through the forms. Since users will be entering those opponent weeks through forms, that would be an easy way to go about it at first. You have control of the forms, so just limit how many opponent_weeks they put in for each Team through forms.

How you'd go about about calling them opponent_week_1 , opponent_week_2 etc.: there are a few ways. I would try putting aa method_missing method in your model (google to see how to do it) then parse the name of the method that you called. Something like this:

def method_missing( method_name )
  if method_name.starts_with?( "opponent_week_" )
    # get the number at the end, then call 
    opponent_weeks[ num_of_week - 1 ]
  else
    super
  end
end

All the best and let me know if you need clarifications.

Answer 2

Take a look here - http://guides.rubyonrails.org/association_basics.html

1. Players <=> Team

class Player < ActiveRecord::Base
...
   belongs_to :team
...
end

class Team < ActiveRecord::Base
...
   has_many :players
...
end

Be sure that migration create_players has field

t.references :team_id

2. Oppenents Youre lead the worsest way. Better take a look at HABTM (has_and_belongs_to_many) relations between commands