创建ruby-on-rails模型

Question

我有一个连接到AS400 DB的现有模型，我需要创建一个类似它的新模型，该模型连接到一个新文件，并提取一个字段(电子邮件地址)，然后循环它5次。这应该不难，但是我从来没有在Ruby中这样做过，而且我似乎不能让它工作。任何能为我指明正确方向的帮助都将不胜感激！

以下是现有的模型：

 class Distributor < ActiveRecord::Base

 establish_connection "as400_#{RAILS_ENV}"
set_table_name "DISTJ01"

# TODO: what to return if no distributor?
# Create array of hashed distributor info.
def self.get_distributors_by_state state, preferred_distributor
    d = []
    # see validate_distributor_number below
    # If they have a preferred distributor, pull that one and make it first so it will default to that.
    if !preferred_distributor.blank?
        s = Distributor.find_by_sql ["SELECT CNAM05 cnam05, CUSNP1 cusnp1 FROM DISTJ01 WHERE CUSNP1 = ?", preferred_distributor]
        d << { :name => s[0].cnam05, :id => s[0].cusnp1 }   unless s.blank?
    end

    # If they have an account number, they can choose to purchase direct in addition to choosing a distributor.
    # Per Ron 4/20/11, removed this.
    #d << { :name => "DIRECT PURCHASE", :id => account_number } unless account_number.blank?

    # Get all other available distributors for this state.
    s = Distributor.find_by_sql ["SELECT CNAM05 cnam05, CUSNP1 cusnp1 FROM DISTJ01 WHERE STATEP2 = ? AND CUSNP1 <> ? ORDER BY CNAM05", state.upcase, preferred_distributor]
    unless s.blank?
        s.each do |t|
            d << { :name => t.cnam05, :id => t.cusnp1 }
        end
    end
    d
end

def self.validate_distributor_number distributor_number, user
    # We need to make sure that the distributor number we are assigning
    # is valid. Since it comes from a form post, somebody could pick
    # another number if they wanted. We can't have that. Granted they
    # already had to logon so they are a legit user, but, they still
    # could try to trick us.
    if distributor_number.strip == user.as400_fields[:account_number].strip
        distributor_number
    else

        # If a DSD account chooses to purchase from their preferred distributor, we use the customer number from
        # the sign-on table, not from the distributor.
        if user.as400_fields[:preferred_distributor] == distributor_number and user.as400_fields[:account_type].strip == "DSD"
            user.as400_fields[:account_number]
        else
            d = Distributor.find_by_sql ["SELECT CUSNP1 cusnp1 FROM DISTJ01, SIGNONS " +
                "WHERE DISTJ01.STATEP2 = SIGNONS.BSSTCDW1 AND SIGNONS.USERW1 = ? AND DISTJ01.CUSNP1 = ?", user.login.upcase, distributor_number]
            d[0].cusnp1 unless d.blank?
        end
    end
end

 end

新连接需要是表WEBOEL23，字段为EMAL23。以下是到目前为止我需要添加的内容：

 class Weboel23 < ActiveRecord::Base

establish_connection "as400_#{RAILS_ENV}"
set_table_name "WEBOEL23"

 def self.get_email_by_account email, cono23
    d = []
    if !emal23.blank?
        s = email.find_by_sql ["SELECT ACT223 act223,EMAL23 emal23 FROM WEBOEL23 WHERE ACT223 = ?", CONO23]         
        d << { :name => s[0].act223, :id => s[0].emal23 }   unless s.blank?
      end    
   end
 end 

模型现在看起来更好了，但是现在在order.rb页面上失败了，当我从模型中调用字段时，我遗漏了什么？

  weboel23 = Weboel23.first(:conditions => {:cusnp1 => distributor_number}, :select => "EMAL23")

Answer 1

鲍勃。你离这里大约10英里！

“连接到新文件”是指新表吗？set_table_name "DISTJ01“似乎设置了表格(正常情况下，表格将自动与型号名称相同)。

模型中现有的两个方法似乎是不相关的。

看起来您的新方法应该只访问emal23并执行逻辑。(但我根本不是一个模范大师。)

或者您的意思是它连接到Distj01表并写入新的文件/表weboel23？

边缘

好吧，我不是一个现有的数据库专家，但我认为您可以在命令行中使用以下命令创建模型

rails generate model

或者，如果您不介意添加更多文件，您可以使用以下命令生成整个mvc

rails generate scaffold

在这两种情况下，您都需要为其指定表名，后跟字段和数据类型

rails generate model Weboel23 emal23:string

如果这样可以，您就可以运行rails控制台了

rails console

然后看一下应用程序，看看有什么。

irb(main):001:0> Weboel23.all

或

> Weboel23.find(1)

查找id为%1的记录

有关rails命令行的信息在此处：http://guides.rubyonrails.org/command_line.html#rails-generate