rails migration code example

Example 1: default value rails migration

t.integer :col_name, :default => 0

Example 2: how create migration rails

rails g migration AddPartNumberToProducts

Example 3: ruby on rails db migrate

rails db:migrate

Example 4: rials db down

bin/rails db:migrate:down VERSION=YYYYMMDDHHMMSS

Example 5: see migration history rails

rake db:migrate:status