两个相似的多对多关系

Question

我有两个类似的 M:M 关系，我分别处理它们，但我不知道如何在不冲突的情况下让它们工作。

关系是玩家和团队

1) 许多球员“为”许多球队“效力”

2) 许多玩家“是”许多团队的成员

class Player < ActiveRecord::Base
  has_many :plays
  has_many :members
  has_many :teams, through: :plays
  has_many :teams, through: :members
end

class Teams < ActiveRecord::Base
  has_many :plays
  has_many :members
  has_many :players, through: :plays
  has_many :players, through: :members
end

class Play < ActiveRecord::Base
  belongs_to :players
  belongs_to :teams
end

class Member < ActiveRecord::Base
  belongs_to :players
  belongs_to :teams
end

我需要能够找到：

Player.find(21).teams #who he plays for
Player.find(21).teams #who he is a member of

Answer 1

您必须为每个has_many 关联指定不同的名称，并使用source 参数指定实际的关联名称。

像这样：

class Player < ActiveRecord::Base
  has_many :plays
  has_many :memberships
  has_many :played_with_teams, through: :plays, source: :team
  has_many :member_of_teams, through: :memberships, source: :team
end

class Team < ActiveRecord::Base
  has_many :plays
  has_many :memberships
  has_many :played_players, through: :plays, source: :player
  has_many :member_players, through: :members, source: :player
end

class Play < ActiveRecord::Base
  belongs_to :player
  belongs_to :team
end

class Membership < ActiveRecord::Base
  belongs_to :player
  belongs_to :team
end

可以这样使用：

Player.find(21).played_with_teams #who he plays for
Player.find(21).member_of_teams #who he is a member of

提示：我更新了答案。