Question

class Sizes < ActiveRecord::Migration
      def self.up
        create_table :sizes do |t|
          t.integer  :size,     :null => false
        end
      end

      def self.down
        drop_table :sizes
      end
end    

class Sizes < ActiveRecord::Migration
      def self.up
        Size.create(:id => 1, :size => 5)
        Size.create(:id => 2, :size => 10)
      end

      def self.down
        Size.delete_all
      end
end

While trying to populate the db using the command rake db:migrate and i got the following output

select * from sizes;
id          size
1           5
2           10

After I rollback the entire tables from db using the command called rake db:rollback. Once again I re-populated the db and now it seems to be the following

select * from sizes;
id          size
3           5
4           10

I don’t want the primary key to change, how do I stop specifying the auto increment capability or specify the ability to associate a hard-coded primary key id, so that it remains the same.

Answer 1

Try this

create_table(:id => false) do |t|
  t.integer :own_id, :options => 'PRIMARY KEY'
end

Hope this helps