Ruby on Rails
TutorialStepOneMigrations

<— TutorialStepOne | Tutorial | TutorialStepTwo —>

Step 1.5 Using Migrations

How to setup your DB using only migrations—the cool way.

Go to TutorialStepTwo and setup your database.yml file appropriately (I know it jumps steps, but hey, no harm done).

go to your “root” directory of your new rails project.

Run ruby script/generate migration firstHack. Edit the file db/migrate/001_first_hack.rb to read

  class FirstHack < ActiveRecord::Migration
    def self.up
      create_table :people do |table|
      # note that "id" is added implicitly, by default
        table.column :name, :string
        table.column :street1, :string
        table.column :street2, :string
        table.column :city, :string
        table.column :state, :string
        table.column :zip, :string

      end
    end

    def self.down
      drop_table :people 
    end
  end

ruby script/generate model Person
    exists  app/models/
    exists  test/unit/
    exists  test/fixtures/
    create  app/models/person.rb
    create  test/unit/person_test.rb
    create  test/fixtures/people.yml
    create  db/migrate
    create  db/migrate/001_create_people.rb

create_table :people do |t|
    t.string :name
    t.string :street1
    t.string :street2
    t.string :city
    t.string :state
    t.string :zip
  t.timestamps
end

rake db:migrate

table.column :name, :string

table.string :name

create_table :people do |table|
    # note that "id" is added implicitly, by default
    table.string :name
    table.string :street1
    table.string :street2
    table.string :city
    table.string :state
    table.string :zip
end

then run rake db:migrate and voila! The table appears. Now we wish to create an entry for superman. To do this let’s create an ActiveRecord entry and save it. Unfortunately this requires us to create a ‘model’ of People first.
run ruby script\generate model Person it creates a “model” which describes person to ActiveRecord, so we can use it.

Now let’s create superman in the Console ruby script/console and enter

      superMan = Person.new
      superMan.name = "Superman" 
      superMan.street1 = "123 Somwhere" 
      superMan.street2 = "" 
      superMan.city = "Smallville" 
      superMan.state = "KS" 
      superMan.zip = "123456" 
      superMan.save

<— TutorialStepOne | Tutorial | TutorialStepThree | or jump directly to TutorialStepFour (Creating a model, already done here) —>