Rails Sort Array By Two Columns

Question

Let's say I have an array called surveys that's made up of Survey.all

Each survey model has a length and cost columns.

What's the best way to sort an array first on length, and then on cost.

I basically want to do something similar to Survey.all.order(length: :desc, cost: :asc) but on the array after it's created.

[**How to sort a ruby array by two conditions**](http://stackoverflow.com/q/29856004/479863) would be another duplicate. — mu is too short, Mar 31 '17 at 02:18

Lenin Raj Rajasekaran · Accepted Answer · 2017-03-31T00:51:25.207

3

surveys.sort_by { |survey| [survey.length, survey.cost] }

If you want to control asc vs desc, just multiply by -1:

surveys.sort_by { |survey| [-1 * survey.length, survey.cost] }

This should work for both regular array of objects or ActiveRecord::Relation

edited Mar 31 '17 at 00:51

answered Mar 31 '17 at 00:39

will that work just on the `surveys` array? At this point in time I will just have access to the array rather than the Survey.all (i.e. I'm not actually using Survey.all to get my array of surveys but it was easier to type) – Tom Hammond Mar 31 '17 at 00:40
should work, try and let me know – Lenin Raj Rajasekaran Mar 31 '17 at 00:41
1

can also use -survey.length for desc. – court3nay Mar 31 '17 at 00:45

1 Answers1