Remove Rails model's fields without crashing on production

If you are experiencing problems after removing an attribute from a Rails model it is probably because ActiveRecord has cached that field, it is something normal is intended to help to improve performance on production environments but when removing a field may cause errors because Rails is training to read/writer a column that doesn't exist anymore, so for Rails 5 and newest we have the `ignore_columns` setting to fix this issue, simply add it to your model something like:

```ruby
class MyModel < ApplicationRecord
  self.ignore_columns = %w[field_to_ignore]
end
```

And you are good to go! if you want to be warned or remind to your team you would like to consider using the strong migrations gem https://github.com/ankane/strong_migrations

ozmar-ugarte
March 1, 2021