title: ruby on rails change default column on Model.find()
body: <p>I have a table with posts and its schema looks like</p>
  
  <pre><code>id | post_id | title | body | etc...
  </code></pre>
  
  <p>Now, when i use</p>
  
  <p><code>Post.find(params[:id])</code></p>
  
  <p>it <strong>searches</strong> the <strong>id column</strong> which is not what i want since i <strong>display the unique</strong> <code>post_id</code> instead of the <code>id</code>...</p>
  
  <p>so how can i make sure the <code>Post.find()</code> will search in <code>post_id</code> column <strong>instead</strong>?</p>