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

Bar graph to show the number of rank from different rank
SELECT Rank, COUNT(Rank) FROM captain GROUP BY Rank
SELECT "Rank", COUNT("Rank") FROM "captain" GROUP BY "Rank"