AWS sdk for .net queryAsync method using global secondary index fails

Question

given below is the method I used to retrieve details from a Dynamodb table. But when I call this method it ended up throwing an exception "Unable to locate property for key attribute appointmentId". primary key of this particular table is appointmentId, but I've already created a global secondary index on patientId column. I'm using that index in below query to get the appointment details by a given patientID.

public async Task GetAppointmentByPatientID(int patientID)
        {
            var context = CommonUtils.Instance.DynamoDBContext;


            PatientAppointmentObjectList.Clear();


            DynamoDBOperationConfig config = new DynamoDBOperationConfig();
            config.IndexName = DBConstants.APPOINTMENT_PATIENTID_GSI;
            AsyncSearch<ScheduledAppointment> appQuery = context.QueryAsync<ScheduledAppointment>(patientID.ToString(), config);
            IEnumerable<ScheduledAppointment> appList = await appQuery.GetRemainingAsync();

            appList.Distinct().ToList().ForEach(i => PatientAppointmentObjectList.Add(i));

            if (PropertyChanged != null)
                this.OnPropertyChanged("PatientAppointmentObjectList");
        }
    }

Answer 1

It was a silly mistake. I've had the hash key column of the table as "appointmentID" and the model object property named as AppointmentID. mismatch in the case of the property name had confused the dynamodb mapping.