how to write a migration to alter a table column from float to bigint in Rails

Question

I have data in a Users table. One column called :provider_user_id of datatype float.

I want to change it to data type bigint.

How should I write this migration in rails 3

The original column was created with the following migration:

class AddFbuidToUsers < ActiveRecord::Migration
  def self.up
    add_column :users, :provider_user_id, :float
  end

  def self.down
    remove_column :users, :provider_user_id
  end
end

Possible duplicate: http://stackoverflow.com/questions/2799774/rails-migration-for-change-column — Simon Perepelitsa, Dec 14 '11 at 11:10

score 5 · Answer 1 · answered May 19 '13 at 17:35

5

change_column :users, :provider_user_id, :bigint

answered May 19 '13 at 17:35

sosiouxme

1,226
16
26

score 0 · Answer 2 · answered Sep 21 '12 at 01:22

Add a new column of type bigint, any name will do.

Write an update loop to update each new bigint column with the value in your current column

Drop the old column (hopefully no RI on it).

Rename the new column to that of the just-dropped old column.

how to write a migration to alter a table column from float to bigint in Rails

2 Answers2