hardMultiple ChoiceObjective-mapped

DP-203 Practice Question: Refer to the exhibit

Exhibit

Azure Stream Analytics job diagnostics log:

{
  "time": "2023-08-01T12:00:00Z",
  "properties": {
    "jobId": "job-123",
    "jobName": "IoTStreamJob",
    "events": [
      {
        "time": "2023-08-01T11:59:00Z",
        "type": "WatermarkDelay",
        "properties": {
          "watermarkDelaySeconds": 120,
          "maxWatermarkDelaySeconds": 300
        }
      },
      {
        "time": "2023-08-01T11:59:30Z",
        "type": "InputDeserializationError",
        "properties": {
          "source": "iothub",
          "count": 15
        }
      }
    ],
    "jobOutputWatermark": "2023-08-01T11:57:00Z"
  }
}

Refer to the exhibit. A Stream Analytics job shows increasing watermark delay and input deserialization errors. Which action should be taken first to troubleshoot?

⚠ Common exam trap

A common mix-up: candidates assume increasing resources (SUs) or adjusting thresholds will fix performance issues, when the real cause is a data format mismatch that prevents any processing from succeeding.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Check the input data schema and ensure it matches the query

Input deserialization errors indicate that the incoming data format does not match the schema defined in the Stream Analytics query. Increasing watermark delay is a symptom of this mismatch, as the job cannot parse events correctly and falls behind. Checking and aligning the input schema with the query is the first and most direct troubleshooting step.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
Check the input data schema and ensure it matches the query
Why this is correct
Deserialization errors are often due to schema mismatch; fixing the data or query resolves the root cause.
✗
Change the output to a different sink
Why it's wrong here
Output sink is unrelated to input deserialization errors.
✗
Increase the number of Streaming Units (SUs)
Why it's wrong here
Scaling may help throughput but does not fix deserialization issues.
✗
Set the watermark delay threshold higher
Why it's wrong here
That only masks the symptom; the underlying issue remains.

Go deeper

DP-203 Practice Question: Refer to the exhibit

Exhibit

Why each option matters

Option-by-option breakdown

Related to this question