问题描述
||
型号代码
class Location < ActiveRecord::Base
attr_accessible :day_tokens,:name,:address,:phone
has_many :locavailability
has_many :dayavailables,:through => :locavailability
attr_reader :day_tokens
def day_tokens=(ids)
self.locavailability.dayavailable_id= ids.split(\",\")
end
end
class Dayavailable < ActiveRecord::Base
has_many :locavailability
has_many :locations,:through => :locavailability
end
class Locavailability < ActiveRecord::Base
attr_accessible :dayavailable_id,:location_id
belongs_to :dayavailable
belongs_to :location
end
数据库列:
locations: id,name,address,phone,hours,created_at,updated_at
dayavailables: id,day,time,updated_at
locavailabilities: id,location_id,dayavailable_id,updated_at
错误
irb(main):004:0> l = Location.find(1)
=> #<Location id: 1,name: \"test\",address: \"123 Fake Street\",phone: \"23443234324\",hours: \"M-F 9 - 5\",created_at: \"2011-05-16 04:56:31\",updated_at: \"2011-05-16 04:56:31\">
irb(main):005:0> l.class
=> Location(id: integer,name: string,address: string,phone: string,hours: string,dentistry_id: integer,created_at: datetime,updated_at: datetime)
irb(main):006:0> l.locavailability
=> []
irb(main):007:0> l.dayavailable_id
NoMethodError: undefined method `dayavailable_id\' for #<Location:0xb6af7c40>
from /usr/lib/ruby/gems/1.8/gems/activemodel-3.0.0/lib/active_model/attribute_methods.rb:364:in `method_missing\'
from /usr/lib/ruby/gems/1.8/gems/activerecord-3.0.0/lib/active_record/attribute_methods.rb:46:in `method_missing\'
from /usr/lib/ruby/gems/1.8/gems/activerecord-3.0.0/lib/active_record/attribute_methods.rb:44:in `send\'
from /usr/lib/ruby/gems/1.8/gems/activerecord-3.0.0/lib/active_record/attribute_methods.rb:44:in `method_missing\'
from (irb):6
Location类不应该访问to3ѭ?我正在github上的railscasts第258集中的代码
我想念什么?
解决方法
为什么
Location
应该可以访问dayavailable_id
?
如果您提供true,则dayavailable_id
是locavailabilities
的列:
数据库列:
位置:ID,名称,地址,电话,小时,created_at,updated_at
可用日期:id,日期,时间,created_at,updated_at
位置可用性:id,location_id,dayavailable_id,created_at,updated_at
尝试这个:
更新
l = Location.find(1)
l.dayavailable_ids #=> Returns an array of the associated objects’ ids
但是,如果您呼叫dayavailable_id
,它应该是表格的一列。
因此,“ 10”将执行以下数据库查询:
select id from dayavailables d
inner join locavailabilities l on l.dayavailable_id = d.id
where l.location_id = 1
但是Locavailability.find(1).dayavailable_id将执行此数据库查询(并非如此,仅是为了提高可读性):
select dayavailable_id from locavailabilities l
where l.location_id = 1