Rashi on Exodus 1:8/רש"י על שמות א׳:ח׳

1ויקם מלך חדש NOW THERE AROSE A NEW KING — Rab and Samuel (two Amoraim or Talmudical teachers) differed in their interpretation of these words. One said that he was really a new king; the other said that it was the same king but he made new edicts (Sotah 11a).

2אשר לא ידע WHO KNEW NOT [JOSEPH] — he comported himself as though he did not know him (Sotah 11a).