CREATE TABLE exhibition_record (Exhibition_ID NUMBER, Date CLOB, Attendance NUMBER)
CREATE TABLE exhibition (Exhibition_ID NUMBER, Year NUMBER, Theme CLOB, Artist_ID NUMBER, Ticket_Price FLOAT)
CREATE TABLE artist (Artist_ID NUMBER, Name CLOB, Country CLOB, Year_Join NUMBER, Age NUMBER)

Show the average of artists' age by country, and sort in desc by the y-axis.
SELECT Country, AVG(Age) FROM artist GROUP BY Country ORDER BY AVG(Age) DESC
SELECT "Country", AVG("Age") FROM "artist" GROUP BY "Country" ORDER BY AVG("Age") DESC