HospitalConnectedLayer.HospitalDAL.AddPerson C# (CSharp) Метод

        public void AddPerson(Person person)
        {
            OpenConnection();
            _command.CommandText =
                "INSERT INTO Persons(FirstName, LastName, DateOfBirth, Address, PolicyNumber) VALUES(@FirstName, @LastName, @DateOfBirth, @Address, @PolicyNumber)";

            _command.Parameters.Add(GetParam("@FirstName", person.FirstName));
            _command.Parameters.Add(GetParam("@LastName", person.LastName));
            _command.Parameters.Add(GetParam("@Address", person.Address));
            _command.Parameters.Add(GetParam("@DateOfBirth", person.DateOfBirth));
            _command.Parameters.Add(GetParam("@PolicyNumber", person.PolicyNumber));

            try
            {
                _command.ExecuteNonQuery();
                //LOGGING
                Logger.Info("Person was added in database");
            }
            catch (SqlException ex)
            {
                //LOGGING
                Logger.Error("This person already exists!",ex);
                throw new InvalidOperationException("This person already exists!");
            }
            catch (Exception ex)
            {
                //LOGGING
                Logger.Error("Can't add person!",ex);
                throw new InvalidOperationException("Can't add person!");
            }
            finally
            {
                CloseConnection();
            }
        }

 public void AddandGetPerson_ThreeDifferentPersons_ShouldPass(Person person)
 {
     var dataStorage = new HospitalDAL(_dataProvider, _connectionString);
     dataStorage.AddPerson(person);
     int personsCount = dataStorage.GetPersons(person.FirstName, person.LastName, person.PolicyNumber).Count;
     Assert.True(personsCount >= 1);
 }