Rails: select unique values from a column

Question

I already have a working solution, but I would really like to know why this doesn\'t work:

ratings = Model.select(:rating).uniq
ratings.each { |r| puts r.rat         


        

Answer 1

Some answers don't take into account the OP wants a array of values

Other answers don't work well if your Model has thousands of records

That said, I think a good answer is:

    Model.uniq.select(:ratings).map(&:ratings)
    => "SELECT DISTINCT ratings FROM `models` " 

Because, first you generate a array of Model (with diminished size because of the select), then you extract the only attribute those selected models have (ratings)