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)
CREATE TABLE exhibition_record (Exhibition_ID NUMBER, Date CLOB, Attendance NUMBER)

What is the number of countries in the artist table?
SELECT Country, COUNT(Country) FROM artist GROUP BY Country
SELECT "Country", COUNT("Country") FROM "artist" GROUP BY "Country"