CREATE TABLE Ship (Ship_ID NUMBER, Name CLOB, Type CLOB, Built_Year FLOAT, Class CLOB, Flag CLOB)
CREATE TABLE captain (Captain_ID NUMBER, Name CLOB, Ship_ID NUMBER, age CLOB, Class CLOB, Rank CLOB)

Plot the average of age by grouped by class as a bar graph, could you show in ascending by the Y-axis?
SELECT Class, AVG(age) FROM captain GROUP BY Class ORDER BY AVG(age)
SELECT "Class", AVG("age") FROM "captain" GROUP BY "Class" ORDER BY AVG("age")