Databricks Databricks-Certified-Professional-Data-Engineer 問題集

質問 1：
A Delta table of weather records is partitioned by date and has the below schema:
date DATE, device_id INT, temp FLOAT, latitude FLOAT, longitude FLOAT
To find all the records from within the Arctic Circle, you execute a query with the below filter:
latitude > 66.3
Which statement describes how the Delta engine identifies which files to load?
A. All records are cached to an operational database and then the filter is applied
B. The Hive metastore is scanned for min and max statistics for the latitude column
C. The Parquet file footers are scanned for min and max statistics for the latitude column
D. The Delta log is scanned for min and max statistics for the latitude column
E. All records are cached to attached storage and then the filter is applied
正解：D
解説: (Topexam メンバーにのみ表示されます)

質問 2：
The data engineering team maintains the following code:

Assuming that this code produces logically correct results and the data in the source table has been de-duplicated and validated, which statement describes what will occur when this code is executed?
A. An incremental job will detect if new rows have been written to the silver_customer_sales table; if new rows are detected, all aggregates will be recalculated and used to overwrite the gold_customer_lifetime_sales_summary table.
B. A batch job will update the gold_customer_lifetime_sales_summary table, replacing only those rows that have different values than the current version of the table, using customer_id as the primary key.
C. The silver_customer_sales table will be overwritten by aggregated values calculated from all records in the gold_customer_lifetime_sales_summary table as a batch job.
D. The gold_customer_lifetime_sales_summary table will be overwritten by aggregated values calculated from all records in the silver_customer_sales table as a batch job.
E. An incremental job will leverage running information in the state store to update aggregate values in the gold_customer_lifetime_sales_summary table.
正解：D
解説: (Topexam メンバーにのみ表示されます)

質問 3：
A Databricks SQL dashboard has been configured to monitor the total number of records present in a collection of Delta Lake tables using the following query pattern:
SELECT COUNT (*) FROM table -
Which of the following describes how results are generated each time the dashboard is updated?
A. The total count of records is calculated from the Delta transaction logs
B. The total count of records is calculated from the Hive metastore
C. The total count of records is calculated from the parquet file metadata
D. The total count of rows is calculated by scanning all data files
E. The total count of rows will be returned from cached results unless REFRESH is run
正解：A
解説: (Topexam メンバーにのみ表示されます)

質問 4：
A table named user_ltv is being used to create a view that will be used by data analysis on various teams.
Users in the workspace are configured into groups, which are used for setting up data access using ACLs.
The user_ltv table has the following schema:

An analyze who is not a member of the auditing group executing the following query:

Which result will be returned by this query?
A. All age values less than 18 will be returned as null values all other columns will be returned with the values in user_ltv.
B. All columns will be displayed normally for those records that have an age greater than 18; records not meeting this condition will be omitted.
C. All records from all columns will be displayed with the values in user_ltv.
D. All columns will be displayed normally for those records that have an age greater than 17; records not meeting this condition will be omitted.
正解：B
解説: (Topexam メンバーにのみ表示されます)

質問 5：
A junior data engineer has configured a workload that posts the following JSON to the Databricks REST API endpoint 2.0/jobs/create.

Assuming that all configurations and referenced resources are available, which statement describes the result of executing this workload three times?
A. The logic defined in the referenced notebook will be executed three times on new clusters with the configurations of the provided cluster ID.
B. Three new jobs named "Ingest new data" will be defined in the workspace, and they will each run once daily.
C. Three new jobs named "Ingest new data" will be defined in the workspace, but no jobs will be executed.
D. The logic defined in the referenced notebook will be executed three times on the referenced existing all purpose cluster.
E. One new job named "Ingest new data" will be defined in the workspace, but it will not be executed.
正解：D
解説: (Topexam メンバーにのみ表示されます)

質問 6：
The data engineer team is configuring environment for development testing, and production before beginning migration on a new data pipeline. The team requires extensive testing on both the code and data resulting from code execution, and the team want to develop and test against similar production data as possible.
A junior data engineer suggests that production data can be mounted to the development testing environments, allowing pre production code to execute against production data. Because all users have Admin privileges in the development environment, the junior data engineer has offered to configure permissions and mount this data for the team.
Which statement captures best practices for this situation?
A. In environments where interactive code will be executed, production data should only be accessible with read permissions; creating isolated databases for each environment further reduces risks.
B. All developer, testing and production code and data should exist in a single unified workspace; creating separate environments for testing and development further reduces risks.
C. Because delta Lake versions all data and supports time travel, it is not possible for user error or malicious actors to permanently delete production data, as such it is generally safe to mount production data anywhere.
D. Because access to production data will always be verified using passthrough credentials it is safe to mount data to any Databricks development environment.
正解：A
解説: (Topexam メンバーにのみ表示されます)