Hmm.. I'm a newbie too, but looking at your XML, it seems the
<instructor_name> has no direct data, instead it has two
child nodes first_name and last_name. Seems you should calling a
function that accepts an object, passing it the
<Instructor_name> object, and in that function concatenating
the children data.
Check out the help section "Using item renderers with the
AdvancedDataGrid control", create and assign a renderer for your
<instructor_name> column, and concatenate the two name fields
inside of the renderer function.
Again, I'm a newbie myself, and I have not tried the
suggestion above, but I hope it points you toward a
solution.