Question

I have model “show” which has_many “performances” and a performance has a certain “location”.
Two or more performances may have the same location.

I’m looking for a way to get all the locations used by the show’s performances, but only once (if there are three performances with location X, I need to get X only once).

Edit: I’m now at this form: an array of objects [[performance_id:1, location_id:1],[performance_id:2, location_id:1],[performance_id:3, location_id:2]] . How can I get an array containing [1,2] (the unique location_id) ?

Answer 1

I added commas to the array:

[
  [performance_id:1, location_id:1],
  [performance_id:2, location_id:1],
  [performance_id:3, location_id:2]  ].flatten.map {|h| h[:location_id]}.uniq

 => [1, 2]