Попробуйте ниже,
Подзапросы поддержки Hive с in/exists/notin/notexists
with avg_age as
(select avg(age) as age1 from table1),
select * from table1 t1, avg_age t2 where t1.age>t2.age.
Или используйте объединения.
select * from table1 t1 inner join
(select avg(age) as age1 from table1) t2
on t1.<UniqCol>=t2.<UniqCol> where t1.age>t2.age.