Making a RAW SQL connection and rendering JSON for custom auto complete field

In any model class:

def self.labels_for_autocomplete(auto_c_req)

   connection.select_all("SELECT label FROM companies WHERE LOWER(label) LIKE '#{auto_c_req.downcase}%' ORDER BY label ASC LIMIT 10 ")

end

connection outpass ActiveRecords and does not cast results as Ruby objects.

in the controller:

def suggest_entreprises

    if request.xhr?
     if request.post?
     auto_c_req=params[:auto_c_req]
     results=Company.labels_for_autocomplete auto_c_req
     render :json => results.to_json
     end
    end
    render :text => "Error"
 end
 

This example renders as JSON, and accepts only POST XHR requests.