Walking encyclopaedia (6-5)
(Other definitions for know-all that I've seen before include "Type of person who wont take advice" , "Wiseacre" , "Smart Aleck" , "Person who behaves like encyclopedia 94-3)" , "Person who thinks he has all the answers" .)
(Other definitions for smarty-pants that I've seen before include "Clever dick" , "Wise guy" , "Clever clogs" .)