In Russian, we say that a new broom sweeps in a new way. In Shemot 1:8 the new broom is the new ruler of Egypt אֲשֶׁ֥ר לֹֽא־יָדַ֖ע אֶת־יוֹסֵֽף who did not know Joseph. We all have been in situations where we had to prove ourselves to the new management, coming to the office with a beehive of new ideas and new plans.
However, the situation in this case is somewhat different. Joseph, as the beginning of the chapter tells us is already dead. Consequently, the Jewish people are trying to use the reputation of the great manager but lo and behold the new boss has no idea who are they talking about. This is only true if we take the story at the face value but commentators agree that here the Torah speaks about the same Pharaoh to whom Joseph served as viceroy.
The commentators are quick to mention the presumes viciousness of the new (old) Pharaoh. According to Rashi, who quotes here Sotah 11a, the Pharaoh behaved as if he did not know Joseph. Here we have an interesting case of interpretation since Bavli says דהוה דמי כמאן דלא ידע ליה כלל, he (thePharaoh) was like someone who did not know him (Joseph) at all. Rashi says, עשה עצמו כאלו לא ידע, he “made himself” like someone who did not know him.
This leap of Rashi is singularly beautiful. The Pharaoh in his interpretation forces himself to distance himself from Joseph. He is not merely passively not recognizing Joseph or giving him a cold shoulder. He actively and consciously behaves like somebody who has no idea about the merits of Joseph thus shaping the entire course of the future for the Jews.