CREATE TABLE Has_Allergy (StuID INT, Allergy VARCHAR)
CREATE TABLE Allergy_Type (Allergy VARCHAR, AllergyType VARCHAR)
CREATE TABLE Student (StuID INT, LName VARCHAR, Fname VARCHAR, Age INT, Sex VARCHAR, Major INT, Advisor INT, city_code VARCHAR)

Show all cities and corresponding number of students by a bar chart, could you order by the bars from low to high?
SELECT city_code, COUNT(*) FROM Student GROUP BY city_code ORDER BY city_code
SELECT "city_code", COUNT(*) FROM "Student" GROUP BY "city_code" ORDER BY "city_code" NULLS FIRST