DP-203 Azure Data Engineer Associate Real-Time Analytics and Streaming Flashcards

Which Azure Stream Analytics compatibility level controls query language features and serialization behaviors?

Answer: Compatibility level

The Compatibility Level setting in a Stream Analytics job defines which version of the query language and runtime behavior to use, with newer levels offering additional features.

In Azure Stream Analytics, what are Streaming Units (SUs)?

Answer: A measure of compute resources (CPU and memory) allocated to a job

Streaming Units represent the amount of CPU and memory resources allocated to a Stream Analytics job, and more SUs allow the job to handle higher event throughput.

Which Delta Lake feature ensures ACID transactions on streaming writes in Azure Databricks?

Answer: Delta transaction log

Delta Lake maintains an ordered transaction log that records every write operation, ensuring ACID compliance even for concurrent streaming and batch writes.

What is the purpose of 'watermarking' in Spark Structured Streaming?

Answer: To handle late-arriving data by defining how long the engine waits before finalizing window aggregates

Watermarking specifies a threshold for how late events can arrive; the engine uses this to determine when a time window's state can be finalized and old state dropped.

In Azure Event Hubs, what is the default message retention period?

Answer: 1 day

By default, Azure Event Hubs retains messages for 1 day, though this can be increased up to 7 days (or 90 days with Event Hubs Premium/Dedicated).

Which Azure Synapse Analytics feature allows real-time analytical queries directly on operational data in Azure Cosmos DB without ETL?

Answer: Synapse Link for Azure Cosmos DB

Azure Synapse Link for Cosmos DB creates an HTAP (Hybrid Transactional/Analytical Processing) connection that automatically syncs Cosmos DB data into the analytical store for zero-ETL querying.