sort_by_last_sign_in.rb

{"draw"=>"2",
 "columns"=>
  {"0"=>
    {"data"=>"auth_method",
     "name"=>"",
     "searchable"=>"true",
     "orderable"=>"false",
     "search"=>{"value"=>"", "regex"=>"false"}},
   "1"=>
    {"data"=>"name",
     "name"=>"",
     "searchable"=>"true",
     "orderable"=>"true",
     "search"=>{"value"=>"", "regex"=>"false"}},
   "2"=>
    {"data"=>"last_sign_in",
     "name"=>"",
     "searchable"=>"true",
     "orderable"=>"true",
     "search"=>{"value"=>"", "regex"=>"false"}},
   "3"=>
    {"data"=>"os",
     "name"=>"",
     "searchable"=>"true",
     "orderable"=>"false",
     "search"=>{"value"=>"", "regex"=>"false"}},
   "4"=>
    {"data"=>"browser",
     "name"=>"",
     "searchable"=>"true",
     "orderable"=>"false",
     "search"=>{"value"=>"", "regex"=>"false"}},
   "5"=>
    {"data"=>"language",
     "name"=>"",
     "searchable"=>"true",
     "orderable"=>"true",
     "search"=>{"value"=>"", "regex"=>"false"}}},
 "order"=>{"0"=>{"column"=>"2", "dir"=>"asc"}},
 "start"=>"0",
 "length"=>"10",
 "search"=>{"value"=>"", "regex"=>"false"},
 "controller"=>"hotspots/users",
 "action"=>"index_data",
 "locale"=>"en",
 "id"=>"0"}