How to restore default Heroku environment variables?

I accidentally cleared all my app's config vars using Heroku documen开发者_JAVA技巧tation (it should have erased only my environment variables and left the ones set by Heroku).

Now my app can't connect to its db (the default shared PostGreSQL) nor its memcache instance.

Do you know how to restore those variables?

Thank you,

Kevin

---

Turns out you can't. I tweeted for help and Heroku support answered me really fast. They restored my PostGreSQL variable and it worked.

I only had to manually remove and re-add the other addons such as Memcached and Campfire deploy hooks.