migration.rb

class CreateCategory < ActiveRecord::Migration
  def change
    create_table :categories do |t|
      t.string :title, null: false
      t.text :description, null: false

      t.timestamps null: false
    end
  end
end

class CreateItem < ActiveRecord::Migration
  def change
    create_table :items do |t|
      t.string :title, null: false
      t.text :description
      t.integer :price, null: false
      t.references :category, null: false
      t.datetime :expire_at, null: false
      t.boolean :validated, null: false, default: true
      t.integer :count_1, null: false
      t.integer :count_2, null: false
      t.integer :count_3, null: false
      t.integer :count_4, null: false

      t.timestamps null: false
    end
  end
end