DP-200 Azure Data Processing and Pipelines 2

Question 1

In Azure Databricks, what is a Delta Lake table?

Accepted Answer

An ACID-compliant storage layer built on Parquet files with a transaction log

Answer

Delta Lake adds ACID transactions, schema enforcement, and time travel to Parquet files by maintaining a JSON transaction log alongside the data.

Question 2

What Azure Databricks feature allows you to query the state of a Delta table at a previous point in time?

Accepted Answer

Time travel

Answer

Delta Lake time travel allows querying historical table versions using VERSION AS OF or TIMESTAMP AS OF syntax.

Question 3

In Azure Databricks, which command is used to optimize a Delta table by compacting small files into larger ones?

Accepted Answer

OPTIMIZE

Answer

The OPTIMIZE command in Delta Lake compacts small Parquet files into larger ones, improving query performance by reducing file overhead.

Question 4

What does the VACUUM command do on a Delta Lake table?

Accepted Answer

Removes old data files no longer referenced by the transaction log

Answer

VACUUM deletes data files older than the retention threshold that are no longer referenced by the Delta transaction log, reclaiming storage.

Question 5

Which Azure service is used to ingest high-velocity streaming data such as telemetry from millions of IoT devices before processing in Azure Databricks?

Accepted Answer

Azure Event Hubs

Answer

Azure Event Hubs is a massively scalable event streaming platform that can ingest millions of events per second for downstream processing.

DP-200 - Microsoft Azure Data Solutions Practice Test

DP-200 - Microsoft Azure Data Solutions Practice Test

DP-200 Azure Data Processing and Pipelines 2