title: How to rake db:migrate on a Heroku staging pipeline?
body: <p>I've setup an app on Heroku, and I've now also set up a pipeline for staging. I did this by creating a fork of my production app on Heroku, then adding this to the app pipeline under the "staging" stage. </p>
  
  <p>Before this (when I only had the app in production), I pushed updates to heroku from the CLI with <code>git push heroku master</code>. I could then update the database for new features with <code>heroku run rake db:migrate</code>.</p>
  
  <p>However, I'm not sure how you would do this with a staging app in a pipeline? I tried using the <code>--remote</code> appendage but it doesn't recognise the app (I think because the <code>--remote</code> was pre pipelines?) </p>
  
  <p>I have auto updates from git setup so that my app-staging always mirrors my git master, and I've just added a new feature which includes a table. The view on the staging site is now returning an error as I haven't run <code>heroku run rake db:migrate</code> on the staging site. </p>
  
  <p>I obviously don't want to push these changes to production without know this new feature works. So how do you do it? Any ideas how to rake db:migrate the pipeline staging database? I can't find any guidance in the heroku manual either :/</p>