inserting issue

i am passing q_no as QueryString in my application.
beginning of the page..i am assigning Request.QueryString["q_no"] to a string. i don't need to do this?
  string q_no = Request.QueryString["q_no"];

i want to insert q_no value to db. 
i tried this   values('q_no')  ....gives me a error..
i tried this   values(q_no)  ....gives me a error..
inside db, q_no datatype is int.
how i insert?