CREATE TABLE PersonFriend (name VARCHAR2, friend VARCHAR2, year NUMBER)
CREATE TABLE Person (name VARCHAR2, age NUMBER, city CLOB, gender CLOB, job CLOB)

Show minimal age from each job, could you order x-axis from low to high order?
SELECT job, MIN(age) FROM Person GROUP BY job ORDER BY job
SELECT "job", MIN("age") FROM "Person" GROUP BY "job" ORDER BY "job"