has_many :through question

According to my book (agile web development with rails 2nd ed)...

class Company < ActiveRecord::Base
  has_many :company_groups
  has_many :groups, :through => :company_groups
  has_many :groups_types, :through => :company_groups, :unique =>
true
end

or

class Company < ActiveRecord::Base
  has_many :company_groups
  has_many :groups, :through => :company_groups
  has_many :groups_types, :through => :company_groups, :select =>
"distinct groups.*"
end

Sorry about the timing, this group is too large to read daily.

Good lord, I think it’s too large/active to +skip+ a day!

RSL