Layout View (Model Designer)
Use Layout view to edit your report model. You can add and delete items from the model and rearrange items within the model. The Report Model tab consists of two sections: Tree view and List view.
The Tree view is displayed in the left pane of the Report Model tab. In Tree view, you can add folders, perspectives, and entities. New folders and entities appear in both the Tree view and the List view. New perspectives only appear in the List view. You can delete, rename, and select model items in Tree view.