title: Make copy of record and save to database but with unique id
body: <p>I am trying to make a new record that is an exact copy of an existing record, but I need the new record to of course to have a unique <code>id</code>.  Meaning: I do not want to copy over the <code>id</code> from the existing record to the new record.</p>
  
  <p>Current code</p>
  
  <pre><code>@blog = Blog.new(title: "some title")
  @blog.save
  
  @copy_of_existing_blog = Blog.new(@blog.attributes)
  @copy_of_existing_blog.save
  </code></pre>
  
  <p>It returns this error:</p>
  
  <blockquote>
    <p>ActiveRecord::RecordNotUnique</p>
  </blockquote>
  
  <p>I understand why it is erroring out.  It is attempting to save a record that has a duplicate <code>id</code> of an existing record.  I just do not know how to make an exact copy of a record, minus the <code>id</code>, and save it to the database.</p>