CREATE TABLE participates_in (stuid DECIMAL, actid DECIMAL)
CREATE TABLE activity (actid DECIMAL, activity_name TEXT)
CREATE TABLE faculty (facid DECIMAL, lname TEXT, fname TEXT, rank TEXT, sex TEXT, phone DECIMAL, room TEXT, building TEXT)
CREATE TABLE student (stuid DECIMAL, lname TEXT, fname TEXT, age DECIMAL, sex TEXT, major DECIMAL, advisor DECIMAL, city_code TEXT)
CREATE TABLE faculty_participates_in (facid DECIMAL, actid DECIMAL)

Which rank has the smallest number of faculty members?
SELECT rank FROM faculty GROUP BY rank ORDER BY COUNT(*) LIMIT 1
SELECT "rank" FROM "faculty" GROUP BY "rank" ORDER BY COUNT(*) NULLS FIRST LIMIT 1