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Description

The oracle-model-generator library is a Ruby library for generating an ActiveRecord model from an existing Oracle table. This will install an "omg" executable that you can use from the command line.

This is aimed at Rails users who are not developing green field applications, but instead are constrained by an existing Oracle database they must conform to.

Synopsis

Using the command line tool:

omg -d your_database -t locations -u some_user -p some_password

The above command results in a file called "location.rb". This is an ActiveRecord model declaration, with all validations, primary keys, table name and belongs_to relationships defined.

If your LOCATIONS table looks like this:

  create table locations(
    location_id number(4,0) primary key,
    street_address varchar2(40), 
    postal_code varchar2(12),
    city varchar2(30) not null
    state_province varchar2(25),
    country_id CHAR(2),
    constraint "LOC_C_ID_FK" FOREIGN KEY (country_id)
      references COUNTRIES (country_id)
  )

The omg library will generate this:

  class Location < ActiveRecord::Base
    set_table_name :locations
    set_primary_key :location_id

    # Table relationships

    belongs_to :countries

    # Validations
    
    validates :location_id, :presence => true, :numericality => {
      :less_than_or_equal_to => 9999, 
      :greater_than_or_equal_to => -9999,
      :only_integer => true
    }

    validates :street_address, :length => {:maximum => 40}
    validates :postal_code, :length => {:maximum => 12}
    validates :city, :length => {:maximum => 30}, :presence => true
    validates :state_province, :length => {:maximum => 25}
    validates :country_id, :length => {:maximum => 2}
  end

It will also generate a corresponding test file using test-unit 2 by default. For the above example you will see some tests like this:

class TC_Location < Test::Unit::TestCase
  def setup
    @location = Location.new
  end

  test 'table name is locations' do
    assert_equal('locations', Location.table_name)
  end

  test 'primary key is location_id' do
    assert_equal('location_id', Location.primary_key)
  end

  test 'location_id basic functionality' do
    assert_respond_to(@location, :location_id)
    assert_nothing_raised{ @location.location_id }
    assert_kind_of(Numeric, @location.location_id)
  end

  test 'location_id must be a number' do
    @location.location_id = 'test_string'
    assert_false(@location.valid?)
    assert_true(@location.errors[:location_id].include?('is not a number'))
  end

  test 'location_id cannot exceed the value 9999' do
    @location.location_id = 10000
    assert_false(@location.valid?)
    assert_true(@location.errors[:location_id].include?('must be less than or equal to 9999'))
  end

  # ... and so on.
end

Maintainer Wanted

I haven't used Oracle in years, and would like to turn it over to someone who is has use for it and is willing to maintain and update it as needed.