This comes across as the author not understanding that traditional RDBMS also cache items in memory. Can Redis beat Postgres or MySQL? Probably, but not by muc

This comes across as the author not understanding that traditional RDBMS also cache items in memory. Can Redis beat Postgres or MySQL? Probably, but not by much if the data is cached by the latter. People are often surprised that the latter can return data in microseconds if the queries and schema are properly designed. Worse, they don’t design their RDBMS properly, and rely solely on a Redis layer for speed. Then, when Redis crashes, is upgraded, etc. their DB falls over because – surprise – they also didn’t properly design their app or DB to handle a thundering herd.