//get user
        public User getUser(string username)
        {
            var user = new User();

            using (var db = new HealthModelsDataContext())
            {
                var query = db.Users.SingleOrDefault(targetUser => targetUser.userName.Equals(username));
                user = query;
            }

            return user;
        }
        //create user
        public void createUser(string firstName, string lastName, string username, string password, string role)
        {
            using (var db = new HealthModelsDataContext())
            {
                var user = new User();

                user.firstName = firstName;
                user.lastName = lastName;
                user.userName = username;
                user.password = password;
                user.role = role;

                db.Users.InsertOnSubmit(user);
                db.SubmitChanges();
            }
        }
        //update user
        public void updateUser(string firstName, string lastName, string username, string password, string role)
        {
            var user = new User();

            using (var db = new HealthModelsDataContext())
            {
                user = db.Users.SingleOrDefault(targetUser => targetUser.userName.Equals(username));

                if(user!=null)
                {
                    user.firstName = firstName;
                    user.lastName = lastName;
                    user.password = password;
                    user.role = role;

                    db.SubmitChanges();
                }
            }
        }
 partial void DeleteUser(User instance);
 partial void UpdateUser(User instance);
 partial void InsertUser(User instance);