When I place a dimension in a drawing view (and a sketch in modelling) it automatically becomes a driving dimension, and in a fully defined sketch/drawing view it flags the "overdefined" error. I am 110% certain that up till fairly recently when I added a dimension to a drawing view the dimension automatically assumed "driven" as opposed to "driving", and when placing dimensions in a fully defined sketch the dimension would automatically become driven so as not to overdefine the sketch.

I assume I have hit some key combo in error, but does anyone have any idea how to make added dimensions automatically become driven in drawing views and or fully defined sketches?