CREATE TABLE sportsinfo (stuid NUMBER, sportname CLOB, hoursperweek NUMBER, gamesplayed NUMBER, onscholarship CLOB)
CREATE TABLE student (stuid NUMBER, lname CLOB, fname CLOB, age NUMBER, sex CLOB, major NUMBER, advisor NUMBER, city_code CLOB)
CREATE TABLE video_games (gameid NUMBER, gname CLOB, gtype CLOB)
CREATE TABLE plays_games (stuid NUMBER, gameid NUMBER, hours_played NUMBER)

Show all advisors who have at least two students.
SELECT advisor FROM student GROUP BY advisor HAVING COUNT(*) >= 2
SELECT "advisor" FROM "student" GROUP BY "advisor" HAVING COUNT(*) >= 2