# File lib/active_record/relation/finder_methods.rb, line 234 def construct_limited_ids_condition(relation) orders = relation.order_values.join(", ") values = @klass.connection.distinct("#{@klass.connection.quote_table_name @klass.table_name}.#{@klass.primary_key}", orders) ids_array = relation.select(values).collect {|row| row[@klass.primary_key]} ids_array.empty? ? raise(ThrowResult) : primary_key.in(ids_array) end