def find_in_batches(options = {})
raise "You can't specify an order, it's forced to be #{batch_order}" if options[:order]
raise "You can't specify a limit, it's forced to be the batch_size" if options[:limit]
start = options.delete(:start).to_i
batch_size = options.delete(:batch_size) || 1000
proxy = scoped(options.merge(:order => batch_order, :limit => batch_size))
records = proxy.find(:all, :conditions => [ "#{table_name}.#{primary_key} >= ?", start ])
while records.any?
yield records
break if records.size < batch_size
last_value = records.last.id
raise "You must include the primary key if you define a select" unless last_value.present?
records = proxy.find(:all, :conditions => [ "#{table_name}.#{primary_key} > ?", last_value ])
end
end