I think aqueduct need provide object transfer method like the AutoMapper

[SinoMiles]

Fetching Only Some Columns/Properties

var query = new Query(context)
..resultingProperties((e) => [e.id, e.name]);
var employees = await query.fetch();

If I just need some Columns. I can definition Class like the following

Class EmployeeOutPutDto{
   String name;
   int age;
}

   var query = new Query<Employee>(context)
    var employees = await query.fetch().tolist();
    var result=Mapper<List<EmployeeOutPutDto>>(employees );
    return result;