 <p>If you don't mind losing all the data, you can run </p> <pre><code>rake db:drop </code></pre> <p>BIG CAVEAT - this will delete your database and all your data.</p> <p>Then you can run</p> <pre><code>rake db:create db:migrate </code></pre> <p>If this is a new app, exists solely on your localhost i.e. has not been deployed to production, and you don't mind losing all your data, then this option is fine.</p> <p>Generally, I would recommend not amending your migrations but creating new ones to change column names etc.</p>