text: CREATE TABLE Caregivers (
      Username varchar(255),
      Salt BINARY(16),
      Hash BINARY(16),
      PRIMARY KEY (Username)
  );
  
  CREATE TABLE Availabilities (
      date varchar(255),
      Care_username varchar(255) REFERENCES Caregivers,
      PRIMARY KEY (date, Care_username)
  );
  
  CREATE TABLE Vaccine (
      Name varchar(255),
      Doses int,
      PRIMARY KEY (Name)
  );
  
  CREATE TABLE Patients (
      Username varchar(255),
      Salt BINARY(16),
      Hash BINARY(16),
      PRIMARY KEY (Username)
  );
  
  
  CREATE TABLE Appointment (
      app_id int,
      vaccine_name varchar(255) REFERENCES Vaccine,
      app_date varchar(255),
      patient_name varchar(255) REFERENCES Patients,
      caregiver_name varchar(255) REFERENCES Caregivers,
      PRIMARY KEY (app_id, vaccine_name)
  );
  
  