0
我有两个Postgres的hstore基于表,entity
和info
,这两者看起来是这样:新手的困惑加入与滑轨
Column | Type | Modifiers
------------+--------------------------+---------------------------------------------------------------
id | integer | not null default nextval('entity__entities_id_seq'::regclass)
created_at | timestamp with time zone | not null
updated_at | timestamp with time zone | not null
context | hstore | default hstore((ARRAY[]::character varying[])::text[])
data | hstore | default hstore((ARRAY[]::character varying[])::text[])
,所以我想执行的SQL查询是这样的:
SELECT e.context->'device' AS device, i.data->'location' AS location from entity AS e
LEFT JOIN info AS i ON e.context->'device' = i.context->'device'
WHERE e.data->'type'='chassis
所以我有两条路:
- 写轨道控制器参考,数据库
- 上ncing一个VIEW写一些轨道喜欢使用包括查询,加入等
我真的喜欢做后者。然而,我对使用rails代码感到困惑。
我的模型是(我知道我失踪belongs_to
等,但我不知道如何使一个hstore领域的关系):
class Device < ActiveRecord::Base
self.table_name = 'entity'
self.primary_key = 'id'
attr_accessible :id, :created_at, :updated_at, :context, :data
serialize :context, ActiveRecord::Coders::Hstore
serialize :data, ActiveRecord::Coders::Hstore
end
class DeviceInfo < ActiveRecord::Base
self.table_name = 'info'
self.primary_key = 'id'
attr_accessible :id, :created_at, :updated_at, :context, :data
serialize :context, ActiveRecord::Coders::Hstore
serialize :data, ActiveRecord::Coders::Hstore
end