CREATE TABLE student (stuid DECIMAL, lname TEXT, fname TEXT, age DECIMAL, sex TEXT, major DECIMAL, advisor DECIMAL, city_code TEXT)
CREATE TABLE voting_record (stuid DECIMAL, registration_date TEXT, election_cycle TEXT, president_vote DECIMAL, vice_president_vote DECIMAL, secretary_vote DECIMAL, treasurer_vote DECIMAL, class_president_vote DECIMAL, class_senator_vote DECIMAL)

Show the advisors of the students whose city of residence has city code 'BAL'.
SELECT advisor FROM student WHERE city_code = "BAL"
SELECT "advisor" FROM "student" WHERE "BAL" = "city_code"