Databricks DATABRICKS-CERTIFIED-PROFESSIONAL-DATA-ENGINEER Online Practice Questions and Exam Preparation

Databricks DATABRICKS-CERTIFIED-PROFESSIONAL-DATA-ENGINEER Online Questions & Answers

• Question 1:

  The viewupdatesrepresents an incremental batch of all newly ingested data to be inserted or updated in thecustomerstable. The following logic is used to process these records.

  

  Which statement describes this implementation?

  A. The customers table is implemented as a Type 3 table; old values are maintained as a new column alongside the current value.
  B. The customers table is implemented as a Type 2 table; old values are maintained but marked as no longer current and new values are inserted.
  C. The customers table is implemented as a Type 0 table; all writes are append only with no changes to existing values.
  D. The customers table is implemented as a Type 1 table; old values are overwritten by new values and no history is maintained.
  E. The customers table is implemented as a Type 2 table; old values are overwritten and new customers are appended.
  B. The customers table is implemented as a Type 2 table; old values are maintained but marked as no longer current and new values are inserted.

• Question 2:

  Each configuration below is identical to the extent that each cluster has 400 GB total of RAM, 160 total cores and only one Executor per VM. Given a job with at least one wide transformation, which of the following cluster configurations will result in maximum performance?

  A. Total VMs; 1 400 GB per Executor 160 Cores / Executor
  B. Total VMs: 8 50 GB per Executor 20 Cores / Executor
  C. Total VMs: 4 100 GB per Executor 40 Cores/Executor
  D. Total VMs:2 200 GB per Executor 80 Cores / Executor
  B. Total VMs: 8 50 GB per Executor 20 Cores / Executor

• Question 3:

  A Delta Lake table was created with the below query:

  

  Consider the following query:

  DROP TABLE prod.sales_by_store If this statement is executed by a workspace admin, which result will occur?

  A. Nothing will occur until a COMMIT command is executed.
  B. The table will be removed from the catalog but the data will remain in storage.
  C. The table will be removed from the catalog and the data will be deleted.
  D. An error will occur because Delta Lake prevents the deletion of production data.
  E. Data will be marked as deleted but still recoverable with Time Travel.
  C. The table will be removed from the catalog and the data will be deleted.

• Question 4:

  A DLT pipeline includes the following streaming tables:

  Raw_lot ingest raw device measurement data from a heart rate tracking device.

  Bgm_stats incrementally computes user statistics based on BPM measurements from raw_lot.

  How can the data engineer configure this pipeline to be able to retain manually deleted or updated records in the raw_iot table while recomputing the downstream table when a pipeline update is run?

  A. Set the skipChangeCommits flag to true on bpm_stats
  B. Set the SkipChangeCommits flag to true raw_lot
  C. Set the pipelines, reset, allowed property to false on bpm_stats
  D. Set the pipelines, reset, allowed property to false on raw_iot
  D. Set the pipelines, reset, allowed property to false on raw_iot

• Question 5:

  When evaluating the Ganglia Metrics for a given cluster with 3 executor nodes, which indicator would signal proper utilization of the VM's resources?

  A. The five Minute Load Average remains consistent/flat
  B. Bytes Received never exceeds 80 million bytes per second
  C. Network I/O never spikes
  D. Total Disk Space remains constant
  E. CPU Utilization is around 75%
  E. CPU Utilization is around 75%

• Question 6:

  A developer has successfully configured credential for Databricks Repos and cloned a remote Git repository. Hey don not have privileges to make changes to the main branch, which is the only branch currently visible in their workspace. Use Response to pull changes from the remote Git repository commit and push changes to a branch that appeared as a changes were pulled.

  A. Use Repos to merge all differences and make a pull request back to the remote repository.
  B. Use repos to merge all difference and make a pull request back to the remote repository.
  C. Use Repos to create a new branch commit all changes and push changes to the remote Git repertory.
  D. Use repos to create a fork of the remote repository commit all changes and make a pull request on the source repository
  C. Use Repos to create a new branch commit all changes and push changes to the remote Git repertory.

• Question 7:

  A platform engineer is creating catalogs and schemas for the development team to use.

  The engineer has created an initial catalog, catalog_A, and initial schema, schema_A. The engineer has also granted USE CATALOG, USE

  SCHEMA, and CREATE TABLE to the development team so that the engineer can begin populating the schema with new tables.

  Despite being owner of the catalog and schema, the engineer noticed that they do not have access to the underlying tables in Schema_A.

  What explains the engineer's lack of access to the underlying tables?

  A. The platform engineer needs to execute a REFRESH statement as the table permissions did not automatically update for owners.
  B. Users granted with USE CATALOG can modify the owner's permissions to downstream tables.
  C. The owner of the schema does not automatically have permission to tables within the schema, but can grant them to themselves at anypoint.
  D. Permissions explicitly given by the table creator are the only way the Platform Engineer could access the underlying tables in their schema.
  C. The owner of the schema does not automatically have permission to tables within the schema, but can grant them to themselves at anypoint.

• Question 8:

  The data architect has mandated that all tables in the Lakehouse should be configured as external Delta Lake tables. Which approach will ensure that this requirement is met?

  A. Whenever a database is being created, make sure that the location keyword is used
  B. When configuring an external data warehouse for all table storage. leverage Databricks for all ELT.
  C. Whenever a table is being created, make sure that the location keyword is used.
  D. When tables are created, make sure that the external keyword is used in the create table statement.
  E. When the workspace is being configured, make sure that external cloud object storage has been mounted.
  C. Whenever a table is being created, make sure that the location keyword is used.

• Question 9:

  The data engineering team maintains a table of aggregate statistics through batch nightly updates. This includes total sales for the previous day alongside totals and averages for a variety of time periods including the 7 previous days, year-todate, and quarter-to-date. This table is namedstore_saies_summaryand the schema is as follows:

  

  The tabledaily_store_salescontains all the information needed to update store_sales_summary. The schema for this table is:

  store_id INT, sales_date DATE, total_sales FLOAT

  Ifdaily_store_salesis implemented as a Type 1 table and thetotal_salescolumn might be adjusted after manual data auditing, which approach is the safest to generate accurate reports in thestore_sales_summarytable?

  A. Implement the appropriate aggregate logic as a batch read against the daily_store_sales table and overwrite the store_sales_summary table with each Update.
  B. Implement the appropriate aggregate logic as a batch read against the daily_store_sales table and append new rows nightly to the store_sales_summary table.
  C. Implement the appropriate aggregate logic as a batch read against the daily_store_sales table and use upsert logic to update results in the store_sales_summary table.
  D. Implement the appropriate aggregate logic as a Structured Streaming read against the daily_store_sales table and use upsert logic to update results in the store_sales_summary table.
  E. Use Structured Streaming to subscribe to the change data feed for daily_store_sales and apply changes to the aggregates in the store_sales_summary table with each update.
  E. Use Structured Streaming to subscribe to the change data feed for daily_store_sales and apply changes to the aggregates in the store_sales_summary table with each update.

• Question 10:

  An upstream system is emitting change data capture (CDC) logs that are being written to a cloud object storage directory. Each record in the log indicates the change type (insert, update, or delete) and the values for each field after the change. The source table has a primary key identified by the fieldpk_id.

  For auditing purposes, the data governance team wishes to maintain a full record of all values that have ever been valid in the source system. For analytical purposes, only the most recent value for each record needs to be recorded. The Databricks job to ingest these records occurs once per hour, but each individual record may have changed multiple times over the course of an hour.

  Which solution meets these requirements?

  A. Create a separate history table for each pk_id resolve the current state of the table by running a union all filtering the history tables for the most recent state.
  B. Use merge into to insert, update, or delete the most recent entry for each pk_id into a bronze table, then propagate all changes throughout the system.
  C. Iterate through an ordered set of changes to the table, applying each in turn; rely on Delta Lake's versioning ability to create an audit log.
  D. Use Delta Lake's change data feed to automatically process CDC data from an external system, propagating all changes to all dependent tables in the Lakehouse.
  E. Ingest all log information into a bronze table; use merge into to insert, update, or delete the most recent entry for each pk_id into a silver table to recreate the current table state.
  E. Ingest all log information into a bronze table; use merge into to insert, update, or delete the most recent entry for each pk_id into a silver table to recreate the current table state.