Azure IoT Developer Exam: AZ-220 Time Series Insight (TSI) Gen2 Solution - Common Mistakes

Common Mistakes in Designing Data Stores for Azure IoT Solution

Question

You work for an automotive manufacturer that already has an Azure IoT solution in place.

The solution collects millions of data from thousands of field equipment like presses, welding robots, conveyors etc.

The quality department wants to add an improvement which provides them with near real-time hints on the trends that are taking shape, so that unfavorable events can be predicted.

You have just started designing the data stores for the new Time Series Insight (TSI) Gen2 solution.

Which two of the following statements are wrong?

Answers

Explanations

Click on the arrows to vote for the correct answer

A. B. C. D. E.

Correct Answers: D, E

Note - The question is asking for TWO WRONG statements.

Option A is an incorrect choice because you can run queries on the warm store with no additional cost.

Option B is an incorrect choice because the minimum retention time of the warm store is 7 days which can be increased up to 30 days.

Option C is an incorrect choice because, unlike the warm store, when running queries against the cold store, additional costs can come up.

Option D is a CORRECT choice because queries against the warm storage are free.

Option E is a CORRECT choice because each Azure Time Series Insight event source must have its dedicated consumer group, not shared with any other consumers.

Otherwise, all readers are at the risk of failures.

Reference:

Time Series Insight (TSI) is a fully managed analytics, storage, and visualization service that makes it simple to explore and analyze billions of IoT events simultaneously. TSI Gen2 is the latest version of the service and is optimized for high-volume, low-latency workloads.

Now, let's evaluate each statement:

A. Querying on the warm storage is free:

This statement is true. In TSI Gen2, querying on warm storage is free. The warm store is the primary store where the latest data is stored and is optimized for low-latency queries. The warm store keeps the most recent data, typically from the last 7-30 days, depending on the storage configuration.

B. The retention time in warm storage is 7-30 days:

This statement is true. The warm store is optimized for low-latency queries and is designed to keep the most recent data, typically from the last 7-30 days, depending on the storage configuration.

C. Querying on the cold storage incurs extra cost:

This statement is true. Cold storage is a lower-cost storage tier that is optimized for long-term data retention. Querying on cold storage incurs an extra cost, and the cost depends on the amount of data queried. Cold storage is intended for infrequent queries and is designed to retain data for longer periods of time, typically months or years.

D. Querying on the warm storage incurs extra cost:

This statement is false. Querying on the warm storage is free in TSI Gen2. The warm store is optimized for low-latency queries and is designed to keep the most recent data, typically from the last 7-30 days, depending on the storage configuration.

E. Multiple TSI event sources can use the same consumer group in IoT Hub:

This statement is true. In Azure IoT Hub, multiple TSI event sources can use the same consumer group. A consumer group is a view of an IoT Hub that provides an independent stream of events to each consumer that is associated with it. Multiple event sources can use the same consumer group to consume events from the same IoT Hub endpoint.

In summary, the two statements that are wrong are:

  • Querying on the warm storage incurs extra cost
  • None of the statements are wrong