Question

我有两个类似的M：M关系，我个人合作但是我不知道如何在没有冲突的情况下工作。

关系是玩家＆amp;队

1）很多玩家都会玩＃34;很多球队

2）许多玩家＆＃34;是＆＃34;的成员。很多球队

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关联指定一个不同的名称，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。

两个类似的多对多关系

1 个答案: