how to sort in grails

[asaidi]

Hi
i have an application created in grails..

class Route {
    Integer prlNo
    String name
    String address
    String address2
    String address3
    String month
    Integer week
    Integer day
    Integer position
    String van
    String period
    Integer rang
    static mapping={
     sort:["rang","day","position"]

    }
    and i have a controller that look for same van to display them
    `def monthly(){
       params.max=10


     def van=params.van

     def res =[route:Route.findAllByVanIlike("${van}%",params),routeCount: Route.count(),sort:"rang",order:"desc"]


   }

when i want to change a position in my table ..
instead of 4 i put it in 1 st..the sort after that not working the forth position is not changed
any help please`

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