Rails Migration for ID Column to Start at 1,000 and Autoincrement Up From There?

Question

I\'d like the ID\'s of my Order model to start at 1000, and count up autoincrementally from there.

Can this be done via migration?

Answer 1

This has not been tested and I am not sure what db you are using.

create_table(:order, :id => false) do |t|
   t.integer :id, :options => 'PRIMARY KEY', :default => 1000

or if you already have the table try this migration

def change
  execute "ALTER TABLE orders AUTO_INCREMENT = 1000"
end

Answer 2

In your migration, after table has been created, update the sequence with something like this:

create_table :products do |t|
  t.string  :name
  # other stuff
end

# for Postgres
execute "SELECT setval('products_id_seq', 1000)"

# and for mysql ...
execute "ALTER TABLE products AUTO_INCREMENT = 1000"