A view that has a root at a type cannot be a standalone view. The view must be a child in an inheritance relationship or the view must have a type relationship with another view. An XML target is invalid if the XML target has no views that are rooted at an element.

You must connect a view with a multiple-occurring view row to another view.

Two views cannot have the same effective view row.

An XML target is invalid if the XML target has no view root at an element.

You can separate parent and child views by other elements, but if you have a choice of two parents for a view, you must use the closest one. Determine the closest parent by the path of the effective view row. One parent comes before the other in the path. Choose the view that comes second in the path.

You must connect all views with the same view root in the same hierarchy. The definition cannot contain multiple trees for the same view root.

An XML view can have a hierarchical relationship to itself if the view row and the view root are identical for the view.