Running Rake Commands
Last updated August 02, 2018
Rake tasks are executed as one-off dynos on Heroku, using the same environment as your app’s dynos. You can run Rake tasks within the remote app environment using the heroku run rake command as follows:
$ heroku run rake db:version
Running `rake db:version` attached to terminal... up, run.1
(in /home/slugs/41913_06f36ef_ab3a/mnt)
Current version: 20081118092504
You can pass Rake arguments, run multiple tasks, and pass environment variables just as you would locally. For instance, to migrate the database to a specific version with verbose backtraces:
$ heroku run rake --trace db:migrate VERSION=20081118092504
After running a migration you’ll want to restart your app with heroku restart to reload the schema and pickup any schema changes.
Limitations
Not all Rake features are supported on Heroku. The following is a list of known limitations:
Rake tasks that write to disk, such as
rake db:schema:dump, are not compatible with Heroku’s ephemeral filesystem.The
db:resettask is not supported. Heroku apps do not have permission to drop and create databases. Use theheroku pg:resetcommand instead.