You may have noticed by now, that in Rails 2.0 changeset 7422, you can specify columns you want to add/remove in your migration by passing attribute:type pairs to the migration generator.

For example, lets assume that we need to add a column ‘role’ in users table(User model). In this case generate a migration like:

script/generate migration AddRoleToUser role:string

Output:

class AddRoleToUser < ActiveRecord::Migration def self.up add_column :users, :role, :string end def self.down remove_column :users, :role end end

Here AddRoleToUser plays the main role. ‘Add’ specifies the we want to add column(s) and ‘User’ separated by ‘To’ specifies the table.

Similarly, if we need to remove a column ‘role’ :

script/generate migration RemoveRoleFromUser role:string

Output:

class RemoveRoleFromUser < ActiveRecord::Migration def self.up remove_column :users, :role end def self.down add_column :users, :role, :string end end

Here RemoveRoleFromUser plays the main role. ‘Remove’ specifies the we want to remove column(s) and ‘User’ separated by ‘From’ specifies the table.

Isn’t it cool?

This entry was posted on Wednesday, January 23rd, 2008 at 12:24 pm and is filed under RubyonRails, Technology, migration, rails, ruby, web development. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.