---
title: "Rails 5 prevents destructive action on production database"
description:
  "Rails 5 prevents destructive action on production database by keeping
  environment version to internal metadata."
canonical_url: "https://www.bigbinary.com/blog/rails-5-prevents-destructive-action-on-production-db"
markdown_url: "https://www.bigbinary.com/blog/rails-5-prevents-destructive-action-on-production-db.md"
---

# Rails 5 prevents destructive action on production database

Rails 5 prevents destructive action on production database by keeping
environment version to internal metadata.

- Author: Hitesh Rawal
- Published: June 7, 2016
- Categories: Rails 5, Rails

Sometimes while debugging production issue mistakenly developers execute
commands like `RAILS_ENV=production rake db:schema:load`. This wipes out data in
production.

Users of heroku download all the config variables to local machine to debug
production problem and sometimes developers mistakenly execute commands which
wipes out production data. This has happened enough number of times to heroku
users that [Richard Schneeman](https://twitter.com/schneems) of heroku decided
to do something about this issue.

## Rails 5 prevents destructive action on production database

Rails 5 [has added](https://github.com/rails/rails/pull/22967) a new table
`ar_internal_metadata` to store `environment` version which is used at the time
of migrating the database.

When the first time `rake db:migrate` is executed then new table stores the
value `production`. Now whenever we load
[database schema](https://github.com/rails/rails/pull/24399) or
[database structure](https://github.com/rails/rails/pull/24484) by running
`rake db:schema:load` or `rake db:structure:load` Rails will check if Rails
environment is "production" or not. If not then Rails will raise an exception
and thus preventing the data wipeout.

To skip this environment check we can manually pass
`DISABLE_DATABASE_ENVIRONMENT_CHECK=1` as an argument with load schema/structure
db command.

Here is an example of running `rake db:schema:load` when development db is
pointing to production database.

```ruby
$ rake db:schema:load

rake aborted!
ActiveRecord::ProtectedEnvironmentError: You are attempting to run a destructive action against your 'production' database.
If you are sure you want to continue, run the same command with the environment variable:
DISABLE_DATABASE_ENVIRONMENT_CHECK=1

```

As we can see Rails prevented data wipeout in production.

This is one of those features which hopefully you won't notice. However if you
happen to do something destructive to your production database then this feature
will come in handy.

## Links

- [Human page](https://www.bigbinary.com/blog/rails-5-prevents-destructive-action-on-production-db)