To define sorting of result dataset, you may use the Sort Type and Sort Order columns of the Columns Pane.
The Sort Type column allows you to specify the way the fields will be sorted - in Ascending or Descending order or not at all.
The Sort Order column allows you to setup the order in which fields will be sorted, in that case that than one field will be used for sorting.
To disable sorting by some field you should clear the Sort Type column for this field.
Defining dataset sorting