CREATE TABLE PersonFriend (name VARCHAR(255), friend VARCHAR(255)); CREATE TABLE Person (age INTEGER, name VARCHAR(255))
Which person whose friends have the oldest average age?
    
SQL: SELECT T2.name, AVG(T1.age) FROM Person AS T1 JOIN PersonFriend AS T2 ON T1.name = T2.friend GROUP BY T2.name ORDER BY AVG(T1.age) DESC LIMIT 1