title: Removing duplicate db migrations from git repository
body: <p>I'm trying to deploy a rails app to Heroku and I'm running into some basic git problems. I'm new to this all -- rails, git, heroku -- so I'm afraid I'm getting lost on what's probably a fairly basic concept.</p>
  
  <p>I've pushed the app to Heroku, but when I'm migrating the db ($ heroku rake db:migrate), I keep getting the following error:</p>
  
  <pre><code>rake aborted!
  Multiple migrations have the name CreateFavorites
  </code></pre>
  
  <p>Checking my github repository, and sure enough, there are two migrations:</p>
  
  <pre><code>20101007030431_create_favorites.rb
  20101012173735_create_favorites.rb
  </code></pre>
  
  <p>The first file -- 20101007030431_create_favorites.rb -- does not exist in my local app, and yet it's still in the github repository after I commit. How can I remove this file and get my repository and local app in sync?</p>
  
  <p>Thanks in advance.</p>