Change integer to float column table Rails

Question

I need to change t.integer :mark_up to a float How can I do this? I have tried in my terminal rails g migration change_column(:stakes, :mark_up, :float) by keep getting a syntax error near unexpected token ('

score 27 · Answer 1 · answered Mar 18 '15 at 04:23

27

In your terminal:

rails generate migration ChangeMarkUpToFloat

and in the file that is created: db/migrate/2015xxxxxxxxxx/change_mark_up_to_float.rb

edit it to:

class ChangeMarkUpToFloat < ActiveRecord::Migration
  def change
    change_column :stakes, :mark_up, :float
  end
end

and then back in your terminal:

rake db:migrate

answered Mar 18 '15 at 04:23

Nosajool

456
4
10

This is ok when the app is not in production. When the app is in production, I would recommend following engineyard's guide on [zero downtime deployment](https://blog.engineyard.com/2011/zero-downtime-deploys-with-migrations) – bsvin33t Mar 23 '15 at 17:49
2

Be careful with using the `change` method when a migration really isn't reversible. If you ran `rake db:migrate:down`, how would it know what type to convert to? Consider defining `up` and `down` instead. – maaachine Feb 16 '16 at 14:31

score 0 · Answer 2 · answered Mar 17 '15 at 21:37

0

You can't use rails code (change_column) in your terminal.

What you need to do is first create the migration: rails generate migration ChangeMarkUpType and then put your rails code in the file that was created.

You can read more about migrations here

answered Mar 17 '15 at 21:37

sebkkom

1,426
17
31

ok i did that and defined change as change_column :stake, :mark_up, :float but my schema still shows that :mark_up is an integer – Neil Murphy Mar 17 '15 at 21:48
1

did you run rake db:migrate? – Nate Beers Mar 17 '15 at 21:49
@NeilMurphy Did you see the migration run? Can you update your question with the code in the migration file? – sebkkom Mar 17 '15 at 22:02

Change integer to float column table Rails

2 Answers2