i know this is duplicate question.i had been gone through many links regarding this.but i m pretty new to wpf and MVVM so i found it difficult to understand.can anyone help me to find simplest way to crete treevview from database using mvvm in wpf.this is my static treeview now. 
I want to feel it from database.i have created table like this
please suggest me any good article or sample code to do it in very easy and understandable maer..please..