repo.rb

class PersonRepository < Norm::PostgreSQLRepository
  
  def named(name)
    select_records(select_statement.where(:name => name)
  end

  def named_ordered_by_created_at(name)
    select_records(select_statement.
                    where(:name => name).
                    order(:created_at, :desc))
  end

  def named_ordered_by_created_at_selecting_foo(:name => name)
     select_records(select_statement(:foo).
                     where(:name => name).
                     order(:created_at, :desc))
  end
  
  #and now we have duplication, so maybe we extract a private method:
  private
  def select(fields, conditions, order)
    #stuff
  end
  #but quickly this method grows unwieldy and we'd like an object that, like us,
  # understands SQL, but unlike us accepts arbitrary valid combinations of
  # selections, projections, groupings etc.
  
   
  def select_statement(*fields)
    Norm::SQL.select(fields).from('people')
  end

  def insert_statement
    column_list = record_class.attribute_names.join(', ')
    Norm::SQL.insert("people (#{column_list})").returning('*')
  end

  def update_statement
    Norm::SQL.update('people').returning('*')
  end

  def delete_statement
    Norm::SQL.delete('people').returning('*')
  end
  
end