Pass Databricks Certified Data Engineer Professional Exam in First Attempt Easily
Real Databricks Certified Data Engineer Professional Exam Questions, Accurate & Verified Answers As Experienced in the Actual Test!

Verified by experts
2 products

You save $34.99

Certified Data Engineer Professional Premium Bundle

  • Premium File 339 Questions & Answers
  • Last Update: Oct 28, 2026
  • Training Course 33 Lectures
$74.99 $109.98

Purchase Individually

  • Premium File

    339 Questions & Answers
    Last Update: Oct 28, 2026

    $76.99
    $69.99
  • Training Course

    33 Lectures

    $43.99
    $39.99

Certified Data Engineer Professional Practice Test 1

Question 1

A partner feed uses intermittent bursts and engineers want ingestion continuity after compute replacement.

Which ingestion result establishes correct file handling?

  1. After restarting, the source file count remains stable and only post-restart arrivals appear as new rows
  2. A malformed fixture is available with its source path and reason while trusted downstream tables exclude it
  3. After a new field appears, schema metadata evolves as designed and both historical and new rows remain queryable
  4. Initial files load once and later runs consume only new objects while retaining the expected checkpoint progress

Explanation

Correct Answer

A:

This directly verifies the intended outcome: after restarting, the source file count remains stable and only post-restart arrivals appear as new rows. The checkpoint determines previously discovered input files and prevents unnecessary reprocessing on recovery. Merely seeing a green job status does not establish that the stated business condition holds.

Incorrect Answers

B:

This would test a different behavior, chiefly retain rescued or quarantined source records with ingestion provenance for targeted remediation. A rescued data column or quarantine path preserves unreadable fields instead of silently dropping evidence. The specific evidence needed here is that after restarting, the source file count remains stable and only post-restart arrivals appear as new rows.

C:

This would test a different behavior, chiefly configure the Auto Loader schema evolution strategy appropriate to the source and production contract. Schema evolution must handle newly observed fields without silently corrupting established column types. The specific evidence needed here is that after restarting, the source file count remains stable and only post-restart arrivals appear as new rows.

D:

This would test a different behavior, chiefly configure Auto Loader with an appropriate cloud-file source and durable schema/checkpoint location. Auto Loader tracks discovered files and incrementally processes newly arrived objects without costly full-directory enumeration. The specific evidence needed here is that after restarting, the source file count remains stable and only post-restart arrivals appear as new rows.

Question 2

A job accumulates streaming delay because each microbatch takes longer than its trigger interval.

Which streaming configuration or processing pattern is the best fit?

  1. Add a watermark on event time and choose a window consistent with allowed lateness
  2. Choose an output mode supported by the stateful aggregation and its target sink
  3. Optimize microbatch processing throughput or scale compute before merely decreasing trigger interval
  4. Use streaming deduplication on business keys with an appropriate event-time watermark

Explanation

Correct Answer

C:

A shorter trigger does not make a slow microbatch run faster and cannot resolve sustained capacity deficits. For this situation, optimize microbatch processing throughput or scale compute before merely decreasing trigger interval. The relevant result would be that peak-load monitoring shows processing throughput exceeds arrival rate and input backlog returns to baseline.

Incorrect Answers

A:

Watermarks bound retained state and govern handling of sufficiently late records in stateful streaming. That option implements add a watermark on event time and choose a window consistent with allowed lateness. It addresses a different problem; here the distinguishing need is to optimize microbatch processing throughput or scale compute before merely decreasing trigger interval.

B:

Append mode cannot emit continually revised aggregates until they are finalized; output mode must match query semantics. That option implements choose an output mode supported by the stateful aggregation and its target sink. It addresses a different problem; here the distinguishing need is to optimize microbatch processing throughput or scale compute before merely decreasing trigger interval.

D:

Stateful deduplication requires key semantics and bounded state to prevent unbounded retention. That option implements use streaming deduplication on business keys with an appropriate event-time watermark. It addresses a different problem; here the distinguishing need is to optimize microbatch processing throughput or scale compute before merely decreasing trigger interval.

Question 3

A media company's bundle installs a Python task that references an artifact absent from the CI runner output.

Which release evidence demonstrates reproducibility and isolation?

  1. The staging deployment touches only staging tables and production remains unchanged
  2. The rollback job runs the previously approved artifact version and restores expected output behavior
  3. A clean CI runner builds the wheel and the deployed task starts without missing-file errors
  4. An unapproved branch cannot deploy production while a signed release passes the controlled pipeline

Explanation

Correct Answer

C:

This directly verifies the intended outcome: a clean CI runner builds the wheel and the deployed task starts without missing-file errors. Bundle deployment must include the expected build outputs and their paths in target configuration. Merely seeing a green job status does not establish that the stated business condition holds.

Incorrect Answers

A:

This would test a different behavior, chiefly move per-environment identifiers into typed bundle variables and target overrides. Environment-specific configuration should be injected at deploy time rather than duplicated in source code. The specific evidence needed here is that a clean CI runner builds the wheel and the deployed task starts without missing-file errors.

B:

This would test a different behavior, chiefly version bundle definitions and artifacts and redeploy a known-good release revision. Immutable source revisions make rollout and rollback auditable and avoid manual guesswork. The specific evidence needed here is that a clean CI runner builds the wheel and the deployed task starts without missing-file errors.

D:

This would test a different behavior, chiefly configure CI/CD branch or release controls and bundle deployment targets with explicit authorization. Separating approvals and target-specific credentials prevents unreviewed code from mutating production resources. The specific evidence needed here is that a clean CI runner builds the wheel and the deployed task starts without missing-file errors.

Question 4

A vendor integration task works in a notebook session but fails on job compute with a secret access error.

Which job-run result demonstrates a successful targeted recovery?

  1. A controlled failed-quality fixture causes the intended condition branch to execute
  2. The service-principal run accesses only its approved secret and completes successfully
  3. The repair completes only the necessary tasks and upstream data is not duplicated
  4. A simulated repeated task leaves exactly one business row per unique source event

Explanation

Correct Answer

B:

This directly verifies the intended outcome: the service-principal run accesses only its approved secret and completes successfully. Interactive and automated runs can differ in principal and dependency context even with identical code. Merely seeing a green job status does not establish that the stated business condition holds.

Incorrect Answers

A:

This would test a different behavior, chiefly inspect task-value references and If/Else condition inputs in the Lakeflow Jobs run details. Branching depends on actual parameter and task-value propagation, which can be inspected per run. The specific evidence needed here is that the service-principal run accesses only its approved secret and completes successfully.

C:

This would test a different behavior, chiefly use Lakeflow Jobs repair to retry failed downstream tasks and review the relevant failure details. Repair runs can preserve eligible successful upstream work while rerunning selected failed tasks. The specific evidence needed here is that the service-principal run accesses only its approved secret and completes successfully.

D:

This would test a different behavior, chiefly make the affected write idempotent and use the job attempt history to identify the replay boundary. Job retry semantics do not roll back external side effects; idempotent keys prevent duplicate commits. The specific evidence needed here is that the service-principal run accesses only its approved secret and completes successfully.

Question 5

A retailer wants a seven-day moving average of revenue while preserving every daily record.

Which analytical SQL expression is most appropriate?

  1. Use SUM with a partitioned ordered cumulative window frame
  2. Use a Spark SQL window aggregate with an explicit ordered frame
  3. Use the LAG window function partitioned by entity and ordered by event sequence
  4. Choose RANK or DENSE_RANK according to whether gaps after ties are acceptable

Explanation

Correct Answer

B:

Window frames compute rolling measures across related rows without collapsing the result like GROUP BY. For this situation, use a Spark SQL window aggregate with an explicit ordered frame. The relevant result would be that each output date retains its row and its rolling value equals the independently calculated test window.

Incorrect Answers

A:

A cumulative window preserves transaction grain while accumulating prior values for each entity. That option implements use SUM with a partitioned ordered cumulative window frame. It addresses a different problem; here the distinguishing need is to use a Spark SQL window aggregate with an explicit ordered frame.

C:

LAG accesses a preceding row in a defined order without requiring an ambiguous self-join. That option implements use the LAG window function partitioned by entity and ordered by event sequence. It addresses a different problem; here the distinguishing need is to use a Spark SQL window aggregate with an explicit ordered frame.

D:

Ranking functions differ in their handling of ties and subsequent rank numbers. That option implements choose RANK or DENSE_RANK according to whether gaps after ties are acceptable. It addresses a different problem; here the distinguishing need is to use a Spark SQL window aggregate with an explicit ordered frame.

Question 6

An external sales team must analyze aggregate partner overlap, but individual rows may never be disclosed.

Which collaboration or federation approach best fits the requirement?

  1. Materialize a governed local Delta copy for frequent heavy analytics instead of relying on remote federation scans
  2. Use a Databricks Clean Room collaboration with controlled queries and output policies
  3. Apply Clean Room query restrictions that limit outputs to permitted aggregate results
  4. Configure Lakehouse Federation using a governed connection and foreign catalog

Explanation

Correct Answer

C:

Controlled computation and output policies are needed to stop identifying raw contributor records. For this situation, apply Clean Room query restrictions that limit outputs to permitted aggregate results. The relevant result would be that attempts to return disallowed identifiers fail while approved aggregate computations complete.

Incorrect Answers

A:

Federation is useful for in-place access, but repeated large remote transfers favor ingestion into optimized local tables. That option implements materialize a governed local Delta copy for frequent heavy analytics instead of relying on remote federation scans. It addresses a different problem; here the distinguishing need is to apply Clean Room query restrictions that limit outputs to permitted aggregate results.

B:

Clean Rooms support collaboration on governed inputs without broadly transferring raw contributing datasets. That option implements use a Databricks Clean Room collaboration with controlled queries and output policies. It addresses a different problem; here the distinguishing need is to apply Clean Room query restrictions that limit outputs to permitted aggregate results.

D:

Federation queries supported external data in place rather than scheduling a full replicated ingestion job. That option implements configure Lakehouse Federation using a governed connection and foreign catalog. It addresses a different problem; here the distinguishing need is to apply Clean Room query restrictions that limit outputs to permitted aggregate results.

Question 7

A medical analytics pipeline executes a complex Pandas transformation with high per-row Python overhead.

Which test outcome best establishes correctness?

  1. Repeated executions with different partition counts return the same row-level identifiers
  2. Identical fixtures produce matching normalized outputs when the shared function runs in both jobs
  3. A test deliberately injecting duplicate rows fails while the reference transformation passes
  4. Batch tests verify schema and values while Spark execution shows a vectorized Python processing path

Explanation

Correct Answer

D:

This directly verifies the intended outcome: batch tests verify schema and values while Spark execution shows a vectorized Python processing path. Pandas UDFs use vectorized transfer and require the declared schema to match the returned values. Merely seeing a green job status does not establish that the stated business condition holds.

Incorrect Answers

A:

This would test a different behavior, chiefly make the transformation deterministic and side-effect-free instead of depending on Python global state. Spark task retries and parallel execution do not preserve a single shared mutable Python process state. The specific evidence needed here is that batch tests verify schema and values while Spark execution shows a vectorized Python processing path.

B:

This would test a different behavior, chiefly implement a pure DataFrame-to-DataFrame function and apply it with DataFrame.transform. Pure DataFrame transformations are reusable and can be tested independently of notebook state. The specific evidence needed here is that batch tests verify schema and values while Spark execution shows a vectorized Python processing path.

C:

This would test a different behavior, chiefly use assertDataFrameEqual on representative fixtures covering duplicate keys and nulls. DataFrame value equality exposes logical row-level changes that task-success status does not prove. The specific evidence needed here is that batch tests verify schema and values while Spark execution shows a vectorized Python processing path.

Question 8

A report executes a broad SELECT but reads many columns that are never used by downstream calculations.

Which optimization is most defensible from the symptoms?

  1. Project only required columns early so the optimizer can prune unneeded data
  2. Investigate key skew and apply supported skew-aware join or salting strategies where justified
  3. Use a broadcast join for an appropriately small and safe dimension when profiling supports it
  4. Inspect query profile and file statistics to tune selective predicates and table layout

Explanation

Correct Answer

A:

Column pruning reduces data read and memory pressure when the storage format supports it. For this situation, project only required columns early so the optimizer can prune unneeded data. The relevant result would be that query profile shows fewer scanned columns and equivalent output on representative data.

Incorrect Answers

B:

Skew creates a few oversized shuffle partitions that dominate stage completion time. That option implements investigate key skew and apply supported skew-aware join or salting strategies where justified. It addresses a different problem; here the distinguishing need is to project only required columns early so the optimizer can prune unneeded data.

C:

Broadcasting a small relation avoids a large shuffle join when memory and size constraints allow. That option implements use a broadcast join for an appropriately small and safe dimension when profiling supports it. It addresses a different problem; here the distinguishing need is to project only required columns early so the optimizer can prune unneeded data.

D:

Poor filter pushdown or clustering can force unnecessary scans even when result cardinality is small. That option implements inspect query profile and file statistics to tune selective predicates and table layout. It addresses a different problem; here the distinguishing need is to project only required columns early so the optimizer can prune unneeded data.

Question 9

A nightly production job fails but owners only notice when a downstream report is missing.

Which alerting design best matches the business threshold?

  1. Configure Lakeflow Jobs failure notifications to an appropriate team destination
  2. Create a Lakehouse alert over a query that tests table freshness and route it to authorized recipients
  3. Use a data-quality query and threshold-based alert on the published table metrics
  4. Set appropriate alert thresholds, evaluation schedules and recipient routing for the intended response

Explanation

Correct Answer

A:

Jobs notifications surface run execution failures without relying on manual inspection of each task. For this situation, configure Lakeflow Jobs failure notifications to an appropriate team destination. The relevant result would be that a forced failure is delivered to the owner channel with job and run context.

Incorrect Answers

B:

Query-based alerts evaluate measurable data conditions rather than depending only on job failure notifications. That option implements create a Lakehouse alert over a query that tests table freshness and route it to authorized recipients. It addresses a different problem; here the distinguishing need is to configure Lakeflow Jobs failure notifications to an appropriate team destination.

C:

Operational success does not prove business completeness; measurable quality thresholds detect low-volume anomalies. That option implements use a data-quality query and threshold-based alert on the published table metrics. It addresses a different problem; here the distinguishing need is to configure Lakeflow Jobs failure notifications to an appropriate team destination.

D:

Well-scoped alert conditions reduce noise while retaining visibility of persistent SLA violations. That option implements set appropriate alert thresholds, evaluation schedules and recipient routing for the intended response. It addresses a different problem; here the distinguishing need is to configure Lakeflow Jobs failure notifications to an appropriate team destination.

Question 10

A marketplace partner runs a non-Databricks engine that implements an open sharing protocol.

Which sharing setup best meets the recipient requirement?

  1. Revoke or update the OpenSharing recipient permissions and verify access is denied
  2. Use Databricks-to-open OpenSharing with an eligible recipient and supported client protocol
  3. Publish an approved share-compatible governed view or data product exposing only the agreed schema
  4. Configure a Databricks-to-Databricks OpenSharing share and recipient for approved assets

Explanation

Correct Answer

B:

Open sharing allows authorized non-Databricks recipients to access shared data through a protocol interface. For this situation, use Databricks-to-open OpenSharing with an eligible recipient and supported client protocol. The relevant result would be that an approved external client reads permitted shared rows and access remains governed by recipient credentials.

Incorrect Answers

A:

Provider-side recipient control stops future access to shared resources without relying on deleting past exports. That option implements revoke or update the OpenSharing recipient permissions and verify access is denied. It addresses a different problem; here the distinguishing need is to use Databricks-to-open OpenSharing with an eligible recipient and supported client protocol.

C:

A curated shared interface separates consumer contracts from internal table shape and sensitive columns. That option implements publish an approved share-compatible governed view or data product exposing only the agreed schema. It addresses a different problem; here the distinguishing need is to use Databricks-to-open OpenSharing with an eligible recipient and supported client protocol.

D:

D2D sharing exposes provider-controlled current data to an authorized Databricks recipient without manual dataset copies. That option implements configure a Databricks-to-Databricks OpenSharing share and recipient for approved assets. It addresses a different problem; here the distinguishing need is to use Databricks-to-open OpenSharing with an eligible recipient and supported client protocol.

Certified Data Engineer Professional Practice Tests

Purchase Individually

  • Premium File

    339 Questions & Answers
    Last Update: Oct 28, 2026

    $76.99
    $69.99
  • Training Course

    33 Lectures

    $43.99
    $39.99

SPECIAL OFFER: GET 10% OFF
This is ONE TIME OFFER

You save
10%

Enter Your Email Address to Receive Your 10% Off Discount Code

SPECIAL OFFER: GET 10% OFF

You save
10%

Use Discount Code:

A confirmation link was sent to your e-mail.

Please check your mailbox for a message from support@examlabs.com and follow the directions.

Download Free Demo of VCE Exam Simulator

Experience Avanset VCE Exam Simulator for yourself.

Simply submit your email address below to get started with our interactive software demo of your free trial.

  • Realistic exam simulation and exam editor with preview functions
  • Whole exam in a single file with several different question types
  • Customizable exam-taking mode & detailed score reports