CREATE TABLE personfriend (name CLOB, friend CLOB, year NUMBER)
CREATE TABLE person (name CLOB, age NUMBER, city CLOB, gender CLOB, job CLOB)

What is the name of the oldest student?
SELECT name FROM person WHERE job = 'student' AND age = (SELECT MAX(age) FROM person WHERE job = 'student')
SELECT "name" FROM "person" WHERE "age" = (SELECT MAX("age") FROM "person" WHERE "job" = 'student') AND "job" = 'student'