Here's a Ruby library (similar to his groupdate gem) I made with an SUM as an additional feature (but no timezones). MySQL and PostgreSQL support https://github

Here's a Ruby library (similar to his groupdate gem) I made with an SUM as an additional feature (but no timezones). MySQL and PostgreSQL support https://github.com/jotto/ar_aggregate_counter/blob/master/lib/ar_aggregate_counter.rb https://github.com/jotto/ar_aggregate_counter/blob/master/li...