writing a Rake task for renaming a field name in a table in a Rails application

Question

I am very new to rails application. I need to change the column name of a table .. SO i browsed thru some sites and as thy mentioned i thought of writing migration file ..

  class RenameNameToFirstnameInUsers < ActiveRecord::Migration
    def self.up
      rename_column 'users', 'name', 'first_name'
    end

    def self.down
        rename_column 'users', 'first_name', 'name'
    end
 end

How to save this file and where ??

applicationname/db/migrate/

In what name i can save this ?? As far now i have seen many files there but all those have prefix of some big_number

And after saving this , how do i test it in my local??

Answer 1

the easiest way to do this is:

Rails3

rails generate migration RenameNameToFirstnameInUsers

Rails2

script/generate migration RenameNameToFirstnameInUsers

And then edit the created migration file, and migrate your db as normal.