Heroku Postgres Rollback
Last updated 17 August 2018
Table of Contents
Heroku Postgres rollback allows you to “roll back” the state of your database to a previous point in time, similar to how heroku releases:rollback allows you to roll back to an older deployment of your application.
Rollback does not affect your primary database, but instead follows the same pattern as fork: it provisions a new database that is not directly connected to the primary in any way. Like a fork, a rollback will take some time to become available.
The rollback period available varies by database plan.
If database credentials have been reset on the primary, rollback will continue to support going back to a point prior to credential reset. Once the fork has been created during the rollback process, a new set of credentials will be created.
Creating a rollback database
Before you roll back, you must ensure the desired rollback point is
available for your database. Different database plans have different
rollback availability. To check rollback availability for your current database, use
the heroku pg:info command:
$ heroku pg:info --app sushi
=== HEROKU_POSTGRESQL_ROSE_URL (DATABASE_URL)
Plan: Standard 0
Status: Available
Data Size: 584.6 MB
Tables: 29
PG Version: 9.2.4
Connections: 8
Fork/Follow: Available
Rollback: from 2013-10-18 20:00 UTC
Created: 2013-04-18 20:14 UTC
Maintenance: not required
Rollback is not available on a new fork for a period after forking, nor on followers for a time after unfollowing.
Creating a rollback database uses the same mechanism as creating a
follower: provisioning occurs
on creation of a new database add-on with the --rollback flag. The --rollback flag can take the config var name of the database on the
same app, an argument of the form appname::HEROKU_POSTGRESQL_COLOR,
or the full URL of any Heroku Postgres database.
In addition, you must specify the time to roll back to. There are two
ways to indicate the desired time: either an explicit timestamp, or a
relative time interval. An explicit timestamp should be of the format 2013-10-22 12:34+00:00, including the time zone offset. You may also use a symbolic time zone. For example, 2013-10-22 12:34 US/Pacific. An interval should be of the
format 3 days 7 hours 22 minutes. A recovery time must be passed
with the --to flag, and a recovery interval with --by. At least
one must be present, but not both. Rollback is not accurate down to the second. Seconds specified in the recovery time or interval are ignored.
A full rollback command looks like this:
$ heroku addons:create heroku-postgresql:standard-0 --rollback HEROKU_POSTGRESQL_YELLOW --to '2013-10-21 15:52+00' --app sushi
The target recovery time (and how long ago this is) will be echoed in the output of the provisioning command.
Preparing a rollback can take anywhere from several minutes to several
hours, depending on the size of your dataset. The heroku pg:wait
command shows the provisioning status of any new databases and can be
used to determine when the rollback is up-to-date:
$ heroku pg:wait --app sushi
Waiting for database HEROKU_POSTGRESQL_YELLOW_URL... available
Deprovisioning
When you are done with the rollback, deprovision it using
heroku addons:destroy:
Be sure to remove the _URL suffix from the database name in this command.
$ heroku addons:destroy HEROKU_POSTGRESQL_YELLOW --app sushi
! WARNING: Destructive Action
! This command will affect the app: sushi
! To proceed, type "sushi" or re-run this command with --confirm sushi
Common use case: Recovery after critical data loss
Rollback is a great safety net in case of a critical data loss issue like accidentally dropping an important table. To recover the lost data through rollback:
-
Create a rollback:
$ heroku addons:create heroku-postgresql:standard-0 --rollback HEROKU_POSTGRESQL_YELLOW --to '2013-10-21 15:52+00' --app sushi Creating heroku-postgresql:standard-0 on ⬢ sushi... $50/month Database will become available after it completes rolling back to 2013-10-21 15:52+0000. Use `heroku pg:wait` to track status. postgresql-adjacent-88888 is being created in the background. The app will restart when complete... Use heroku addons:info postgresql-adjacent-88888 to check creation progress Use heroku addons:docs heroku-postgresql to view documentation -
Confirm that the rollback is up-to-date:
$ heroku pg:wait --app sushi Waiting for database HEROKU_POSTGRESQL_SILVER... available -
Promote the rollback as the primary database
$ heroku pg:promote HEROKU_POSTGRESQL_SILVER --app sushi -
Re-establish replication on all followers to the new leader (if applicable)
$ heroku addons:create heroku-postgresql:standard-2 --follow HEROKU_POSTGRESQL_SILVER --app sushi Adding heroku-postgresql:standard-2 to sushi... done, v71 ($200/mo) Attached as HEROKU_POSTGRESQL_WHITE Follower will become available for read-only queries when up-to-date Use `heroku pg:wait` to track status