has_many :through - Self-referential has_many :through associations

has_many :through - Self-referential has_many :through associations

Update: This article is now superceded by a new version that is updated for Rails 2.0 changes. He...概要を表示 Update: This article is now superceded by a new version that is updated for Rails 2.0 changes. Here we go. Rick Olson helped me figure out how to do bi-directional, self-referential associations using has_many :through. It's not obvious (until you know the trick), so here's how it's done. This example is for modeling digraphs. create_table "nodes" do |t| t.column "name", :string t.column "capacity

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