Ruby on rails 3 与Rails 3中遗留数据库的简单关联？

我正在处理一个遗留数据库，同时也在阅读Rails

我有两个模型。

日记

模型和

动物

模型

日记.rb

class Diary < ActiveRecord::Base
  establish_connection :premvet

  attr_accessible :DiaryNo ,:DiaryName, :DiaryDate, :SlotHour, :TotalSlots, :BlockSlots, :BlockBooked, :FreeSlot, :BookedSlot

  self.table_name = 'diary'
  self.primary_key = 'DiaryNo'

  has_many :animals, :foreign_key => 'DiaryQueue'
end

class Animal < ActiveRecord::Base
  establish_connection :premvet

  self.table_name = 'animal'
  self.primary_key = 'PVID'

  attr_accessible :AddedBy, :Age, :AnimalBFAmount, :AnimalBalance, :AnimalName, :Archive, :BillType, :Breed, :ChronicStatus, :Class, :Classification, :ClientKey, :Colour, :Date1, :DateOfBirth, :DateofBirth, :Dead, :DiaryQueue, :DiscField, :DrugsAtCost, :DrugsNoVAT, :ESDAmount, :ESDType, :FNote, :FirstRegisteredDate, :Height, :IDNumber, :Insured, :InsuredWith, :IsClient, :IsClientDate, :IsMaster, :LastBilledAmount, :LastBilledDate, :LastConsDate, :LastContributionDate, :LastPaidDate, :LastWeightDate, :Locked, :LoyaltyMultiplier, :LoyaltyPoints, :MR_Flag_0, :MR_Flag_1, :MR_Flag_10, :MR_Flag_11, :MR_Flag_12, :MR_Flag_13, :MR_Flag_14, :MR_Flag_15, :MR_Flag_2, :MR_Flag_3, :MR_Flag_4, :MR_Flag_5, :MR_Flag_6, :MR_Flag_7, :MR_Flag_7, :MR_Flag_8, :MR_Flag_9, :Mileage, :Neutered, :NextApptDate, :ORT, :OldSex, :Opt_Flag_0, :Opt_Flag_1, :Opt_Flag_2, :Opt_Flag_3, :Opt_Flag_4, :Opt_Flag_5, :Opt_Flag_6, :Opt_Flag_7, :PVID, :PreferredContact, :PreferredUser, :Ref1, :RefPrac, :ReferredBy, :SSDType, :SeenInPeriod, :SendBill, :Sex, :SiteAnimal, :Species, :Status, :SurcAmount, :SurcType, :SurgeryNumber, :TBU, :TOSAmount, :TOSDrugs, :TOSFees, :TOSType, :Weight

  belongs_to :client, :foreign_key => 'ClientKey'
  belongs_to :diary, :foreign_key => 'DiaryNo'
end

@animates\u todayspaints

方法如下所示：

def appointments
    @animals_todaysappointments = Animal.where('DATE(NextApptDate) = ?', Date.today).page(params[:page]).per_page(15).order('NextApptDate ASC')
    respond_to do |format|
      format.html # index.html.erb
    end
  end

如果我加上：

delegate :DiaryName, :to => :diary

对于动物模型，我得到以下错误：

Animal#DiaryName delegated to diary.DiaryName, but diary is nil: #

每个动物记录的日记队列值介于0和10之间，日记表有许多行，例如：

DiaryNo  DiaryName  DiaryDate  SlotHour  TotalSlots  BlockBooked  FreeSlot  BookedSlot
--------------------------------------------------------------------------------------
1        Morning    2012-07-16 9         18          0            0         18

有些行具有相同的日记编号，但它们也具有相同的日记名称。只有日记日期、SlotHour、TotalSlots、BlockBooked、FreeSlot和BookedSlots在这些行中改变

为了尝试防止出现错误，我在视图中添加了以下内容：

<% unless animal.DiaryName.nil? %>
 <td><%= animal.DiaryName %></td>
<% else %>
 <td><%= animal.DiaryQueue %>
<% end %>  

---

我做错了什么？

根据以上答案，您可能需要将Animal中的“归属”方法更改为以下内容：

belongs_to :diary, :foreign_key => "DiaryQueue", :primary_key => "DiaryNo"

---

在您当前的实现中，您的模型将尝试将

Animal#DiaryNo

与

Diary#DiaryNo

进行匹配，而您所说的是将

Animal#DiaryQueue

与

Diary#DiaryNo
进行匹配，您说它失败了，但出现了异常错误。你能发布所引发的全部异常吗？抱歉，只是在我的问题中添加了它。似乎找不到动物记录的相关日记（Dairy？）记录。你确定记录在那里吗？动物记录有一个日记队列值，它与日记表中的日记号匹配。日记表只是一个“查找/引用”表，如中所示，我正在使用它将日记队列的值转换为日记名。那太好了，谢谢，我没有意识到你可以设置外键和主键。谢谢
Animal#DiaryName delegated to diary.DiaryName, but diary is nil: #

DiaryNo  DiaryName  DiaryDate  SlotHour  TotalSlots  BlockBooked  FreeSlot  BookedSlot
--------------------------------------------------------------------------------------
1        Morning    2012-07-16 9         18          0            0         18

<% unless animal.DiaryName.nil? %>
 <td><%= animal.DiaryName %></td>
<% else %>
 <td><%= animal.DiaryQueue %>
<% end %>  

Animal#DiaryName delegated to diary.DiaryName, but diary is nil: #

belongs_to :diary, :foreign_key => "DiaryQueue", :primary_key => "DiaryNo"