Postgresql Rails: select a random entry within a specific range?

Question

I have the following code in my controller to select a random photo:

@photo1 = @contest.photos.limit(1).order("RANDOM()")

I want to select another random photo as @ photo2, but its rating attribute must be +/- 400 from @ photo1 rating. How should I do it?

Optional: I prefer @ photo2 to be within +/- 200 @ photo1, and if not, search +/- 400

+3

2paws May 18 '15 at 3:34 am

1 answer

max · Accepted Answer · 2015-05-18T04:25:21+0000

You can use where

with a range to create a BETWEEN statement.

Photo.where(score: ((@photo1.score-200)..(@photo1.score+200)))
     .order("RANDOM()").take