title: how can i insert data into table by the help of migration and that table is generated previously through another migration
body: <p>I have a role table with user name and role and company. I want to insert data into that table through a new migration file so how can i do this?</p>
  
  <p>I got a code like this but how can i use it and where i am not able to understand.</p>
  
  <pre><code>class Foo &lt; ActiveRecord::Migration
    def self.up
      Users.new(:username =&gt; "Hello", :role =&gt; "Admin")
    end
    def self.down
      Users.delete_all(:username =&gt; "Hello")
    end
  end
  </code></pre>