Walking encyclopaedia? (4-3)

I think it could be either:

Which length description are you looking for?:

4-3

6-5

know-all

(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" .)

I've seen this clue in The Guardian.

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