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I want to restructure the query below using Squeel. I'd like to do this so that I can chain the operators in it and re-use the logic in the different parts of the query. User.find_by_sql("SELECT users.*, users.computed_metric, users.age_in_seconds, ( users.computed_metric / age_in_seconds) as compound_computed_metric from ( select users.*, (users.id *2 ) as computed_metric, (extract(epoch from now()) - extract(epoch from users.created_at) ) as age_in_seconds from users ) as users") The query has to all operate in the DB and should not be a hybrid Ruby solution since it has to order and slice millions of records. I've set the problem up so that it should run against a normal user table and so that you can play with the alternatives to it. Restrictions on an acceptable answer the query should return a User object with all the normal attributes each user object should also include extra_metric_we_care_about , age_in_seconds and compound_computed_metric the query should not duplicate any logic by just printing out a string in multiple places - I want to avoid doing the same thing twice [updated] The query should all be do-able in the DB so that a result set that may consist of millions of records can be ordered and sliced in the DB before returning to Rails [updated] The solution should work for a Postgres DB Example of the type of solution I'd like The solution below doesn't work but it shows the type of elegance that I'm hoping to achieve class User < ActiveRecord::Base # this doesn't work - it just illustrates what I want to achieve def self.w_all_additional_metrics select{ ['*', computed_metric, age_in_seconds, (computed_metric / age_in_s

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