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

Bar graph to show the number of rank from different rank, and display by the Rank in descending.
SELECT Rank, COUNT(Rank) FROM captain GROUP BY Rank ORDER BY Rank DESC
SELECT "Rank", COUNT("Rank") FROM "captain" GROUP BY "Rank" ORDER BY "Rank" DESC NULLS LAST