you can easily drag the top and bottom faces of your model to make a sync edit. talking about your jpeg. if your dragged the bottom you would simply extend the length of the circular face thus extending the length of the cylinder. if you dragged the top face you have a few options: based on your intent and selection from the command bar you can continue the surface (wrap the sides up and inward continuing the outer profile as the tip moves up) or pull it off normal with the vector of the move thus creating a "straight" protrusion base on the profile of the top face.
but for your example of a hole. NO, you can not stretch a hole into a slot this would required additional faces to be created and we do not do that.
Matt Johnson Application Engineer Ally PLM Solutions firstname.lastname@example.org http://allyplm.com/