CREATE TABLE personfriend (name TEXT, friend TEXT, year DECIMAL)
CREATE TABLE person (name TEXT, age DECIMAL, city TEXT, gender TEXT, job TEXT)

Find the name and age of the person who is a friend of both Dan and Alice.
SELECT T1.name, T1.age FROM person AS T1 JOIN personfriend AS T2 ON T1.name = T2.name WHERE T2.friend = 'Dan' INTERSECT SELECT T1.name, T1.age FROM person AS T1 JOIN personfriend AS T2 ON T1.name = T2.name WHERE T2.friend = 'Alice'
SELECT "T1"."name", "T1"."age" FROM "person" AS "T1" JOIN "personfriend" AS "T2" ON "T1"."name" = "T2"."name" AND "T2"."friend" = 'Dan' INTERSECT SELECT "T1"."name", "T1"."age" FROM "person" AS "T1" JOIN "personfriend" AS "T2" ON "T1"."name" = "T2"."name" AND "T2"."friend" = 'Alice'