Question

我正在尝试将以下Hash传递给Active Record以保存：

[{
  "id"=>"WSECOUT", 
  "realtime_start"=>"2013-02-10", 
  "realtime_end"=>"2013-02-10", 
  "title"=>"Reserve Bank Credit - Securities Held Outright", 
  "observation_start"=>"1989-03-22", 
  "observation_end"=>"2013-02-06", 
  "frequency"=>"Weekly, Ending Wednesday", 
  "frequency_short"=>"W", 
  "units"=>"Billions of Dollars", 
  "units_short"=>"Bil. of $", 
  "seasonal_adjustment"=>"Not Seasonally Adjusted", 
  "seasonal_adjustment_short"=>"NSA", 
  "last_updated"=>"2013-02-08 08:32:33-06", 
  "popularity"=>"42", 
  "notes"=>"The amount of securities held by Federal Reserve Banks. This quantity is the cumulative result of permanent open market operations: outright purchases or sales of securities, conducted by the Federal Reserve. Section 14 of the Federal Reserve Act defines the securities that the Federal Reserve is authorized to buy and sell."
  }]

我的红宝石课程看起来像这样：

require 'rubygems'
require 'active_record'  
require 'logger'

ActiveRecord::Base.establish_connection(  
:adapter => "mysql2",  
:host => "localhost",  
:username => "root",
:password => "*********",
:database => "fred"  
)  

class Series < ActiveRecord::Base

  attr_accessible :id, :realtime_start, :realtime_end, :title, :observation_start,
              :observation_end, :frequency, :frequency_short, :units, :units_short, 
              :seasonal_adjustment, :seasonal_adjustment_short, :last_updated, 
              :popularity, :notes

end

require_relative 'wsecout'
@series = Wsecout.new.getSeries "wsecout"
@series = @series['series']

test = Series.create(@series)

@series变量包含Hash。当我运行此代码时，对象的创建与mysql中的行一样，但是，字段中没有数据。我知道我在这里错过了一步，但我无法弄清楚哪一步。另外，我的Hash是否存在包含id的问题，因为Active Record会创建它自己的id？

Answer 1

回答你的第二个问题“将”id“映射到名为：series_id的新字段：

@series['series'][0]['series_id'] = @series['series'][0]['id']
@series['series'][0].delete('id')

或者，如果您想根据某些条件更改多个密钥，请在if条件中使用它，如下所示：

@series['series'][0].keys.each do |k|
  if(k == 'id')
    @series['series'][0]['series_id'] = @series['series'][0][k]
    @series['series'][0].delete(k)
  end
end

这会迭代哈希的每个键，如果密钥与id匹配，那么它会添加另一个具有相同值的密钥series_id并删除id。

没有Rails的Active Record：如何将任意哈希传递给Active Record

1 个答案: