CREATE TABLE Allergy_Type (Allergy VARCHAR2, AllergyType VARCHAR2)
CREATE TABLE Has_Allergy (StuID NUMBER, Allergy VARCHAR2)
CREATE TABLE Student (StuID NUMBER, LName VARCHAR2, Fname VARCHAR2, Age NUMBER, Sex VARCHAR2, Major NUMBER, Advisor NUMBER, city_code VARCHAR2)

How many students have each different allergy. Show bar chart.
SELECT Allergy, COUNT(*) FROM Has_Allergy GROUP BY Allergy
SELECT "Allergy", COUNT(*) FROM "Has_Allergy" GROUP BY "Allergy"