【11-17】【博睿项目】has_and_belongs_to_many【连接表不使用默认的id】
2010-12-01 21:43
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表: keywords categories_keywords categories
id keyword_id category_dn category_dn
class Keyword:
has_and_belongs_to_many :categories,
:association_foreign_key => "category_dn"
class Category:
has_and_belongs_to_many :keywords,
:foreign_key => "category_dn"
rails仍然使用的是自动增长的整数
要写sql语句覆盖:finder_sql :counter_sql :delete_sql :insert_sql ?
要使用其他字段(如:string) 且链接表中有其他信息字段使用through
class Category < ActiveRecord::Base
has_many :category_keyword_items
has_many :keywords, :through => :category_keyword_items
end
class Keyword < ActiveRecord::Base
has_many :category_keyword_items
has_many :catrgories, :through => :category_keyword_items
end
class CategoryKeywordItem < ActiveRecord::Base
belongs_to :cetegory
belongs_to :keyword
end
id keyword_id category_dn category_dn
class Keyword:
has_and_belongs_to_many :categories,
:association_foreign_key => "category_dn"
class Category:
has_and_belongs_to_many :keywords,
:foreign_key => "category_dn"
rails仍然使用的是自动增长的整数
要写sql语句覆盖:finder_sql :counter_sql :delete_sql :insert_sql ?
要使用其他字段(如:string) 且链接表中有其他信息字段使用through
class Category < ActiveRecord::Base
has_many :category_keyword_items
has_many :keywords, :through => :category_keyword_items
end
class Keyword < ActiveRecord::Base
has_many :category_keyword_items
has_many :catrgories, :through => :category_keyword_items
end
class CategoryKeywordItem < ActiveRecord::Base
belongs_to :cetegory
belongs_to :keyword
end
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