Databricks-Certified-Professional-Data-Engineer試験無料問題集（122題）「Databricks Certified Professional Data Engineer 認定」

出題：1

A table named user_ltv is being used to create a view that will be used by data analysts 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:
email STRING, age INT, ltv INT
The following view definition is executed:

An analyst who is not a member of the marketing group executes the following query:
SELECT * FROM email_ltv
Which statement describes the results returned by this query?

A. Three columns will be returned, but one column will be named "redacted" and contain only null values.

B. Only the email and ltv columns will be returned; the email column will contain the string "REDACTED" in each row.

C. Only the email and itv columns will be returned; the email column will contain all null values.

D. The email, age. and ltv columns will be returned with the values in user ltv.

E. The email and ltv columns will be returned with the values in user itv.

正解：B 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

出題：2

Which statement describes the correct use of pyspark.sql.functions.broadcast?

A. It marks a column as small enough to store in memory on all executors, allowing a broadcast join.

B. It caches a copy of the indicated table on attached storage volumes for all active clusters within a Databricks workspace.

C. It marks a column as having low enough cardinality to properly map distinct values to available partitions, allowing a broadcast join.

D. It caches a copy of the indicated table on all nodes in the cluster for use in all future queries during the cluster lifetime.

E. It marks a DataFrame as small enough to store in memory on all executors, allowing a broadcast join.

正解：E 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

出題：3

A data ingestion task requires a one-TB JSON dataset to be written out to Parquet with a target part-file size of 512 MB. Because Parquet is being used instead of Delta Lake, built-in file-sizing features such as Auto-Optimize & Auto-Compaction cannot be used.
Which strategy will yield the best performance without shuffling data?

A. Set spark.sql.adaptive.advisoryPartitionSizeInBytes to 512 MB bytes, ingest the data, execute the narrow transformations, coalesce to 2,048 partitions (1TB*1024*1024/512), and then write to parquet.

B. Set spark.sql.shuffle.partitions to 512, ingest the data, execute the narrow transformations, and then write to parquet.

C. Ingest the data, execute the narrow transformations, repartition to 2,048 partitions (1TB* 1024*1024/512), and then write to parquet.

D. Set spark.sql.shuffle.partitions to 2,048 partitions (1TB*1024*1024/512), ingest the data, execute the narrow transformations, optimize the data by sorting it (which automatically repartitions the data), and then write to parquet.

E. Set spark.sql.files.maxPartitionBytes to 512 MB, ingest the data, execute the narrow transformations, and then write to parquet.

正解：D 解答を投票する

出題：4

A Delta Lake table in the Lakehouse named customer_parsams is used in churn prediction by the machine learning team. The table contains information about customers derived from a number of upstream sources. Currently, the data engineering team populates this table nightly by overwriting the table with the current valid values derived from upstream data sources.
Immediately after each update succeeds, the data engineer team would like to determine the difference between the new version and the previous of the table.
Given the current implementation, which method can be used?

A. Execute a query to calculate the difference between the new version and the previous version using Delta Lake's built-in versioning and time travel functionality.

B. Parse the Spark event logs to identify those rows that were updated, inserted, or deleted.

C. Execute DESCRIBE HISTORY customer_churn_params to obtain the full operation metrics for the update, including a log of all records that have been added or modified.

D. Parse the Delta Lake transaction log to identify all newly written data files.

正解：A 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

出題：5

Which distribution does Databricks support for installing custom Python code packages?

A. Wheels

B. CRAM

C. nom

D. sbt

E. jars

F. CRAN

正解：C 解答を投票する

出題：6

Although the Databricks Utilities Secrets module provides tools to store sensitive credentials and avoid accidentally displaying them in plain text users should still be careful with which credentials are stored here and which users have access to using these secrets.
Which statement describes a limitation of Databricks Secrets?

A. The Databricks REST API can be used to list secrets in plain text if the personal access token has proper credentials.

B. Iterating through a stored secret and printing each character will display secret contents in plain text.

C. Because the SHA256 hash is used to obfuscate stored secrets, reversing this hash will display the value in plain text.

D. Secrets are stored in an administrators-only table within the Hive Metastore; database administrators have permission to query this table by default.

E. Account administrators can see all secrets in plain text by logging on to the Databricks Accounts console.

正解：A 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

出題：7

A Data engineer wants to run unit's tests using common Python testing frameworks on python functions defined across several Databricks notebooks currently used in production.
How can the data engineer run unit tests against function that work with data in production?

A. Run unit tests against non-production data that closely mirrors production

B. Define units test and functions within the same notebook

C. Define and unit test functions using Files in Repos

D. Define and import unit test functions from a separate Databricks notebook

正解：A 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

出題：8

The data engineer is using Spark's MEMORY_ONLY storage level.
Which indicators should the data engineer look for in the spark UI's Storage tab to signal that a cached table is not performing optimally?

A. Size on Disk is> 0

B. On Heap Memory Usage is within 75% of off Heap Memory usage

C. The RDD Block Name included the '' annotation signaling failure to cache

D. The number of Cached Partitions> the number of Spark Partitions

正解：C 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

出題：9

A data architect has heard about lake's built-in versioning and time travel capabilities. For auditing purposes they have a requirement to maintain a full of all valid street addresses as they appear in the customers table.
The architect is interested in implementing a Type 1 table, overwriting existing records with new values and relying on Delta Lake time travel to support long-term auditing. A data engineer on the project feels that a Type 2 table will provide better performance and scalability.
Which piece of information is critical to this decision?

A. Shallow clones can be combined with Type 1 tables to accelerate historic queries for long-term versioning.

B. Delta Lake time travel does not scale well in cost or latency to provide a long-term versioning solution.

C. Delta Lake time travel cannot be used to query previous versions of these tables because Type 1 changes modify data files in place.

D. Data corruption can occur if a query fails in a partially completed state because Type 2 tables requires

正解：B 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

出題：10

The data engineer team has been tasked with configured connections to an external database that does not have a supported native connector with Databricks. The external database already has data security configured by group membership. These groups map directly to user group already created in Databricks that represent various teams within the company.
A new login credential has been created for each group in the external database. The Databricks Utilities Secrets module will be used to make these credentials available to Databricks users.
Assuming that all the credentials are configured correctly on the external database and group membership is properly configured on Databricks, which statement describes how teams can be granted the minimum necessary access to using these credentials?

A. "Read" permissions should be set on a secret scope containing only those credentials that will be used by a given team.

B. "Manage" permission should be set on a secret scope containing only those credentials that will be used by a given team.

C. No additional configuration is necessary as long as all users are configured as administrators in the workspace where secrets have been added.

D. ''Read'' permissions should be set on a secret key mapped to those credentials that will be used by a given team.

正解：A 解答を投票する

解説: (GoShiken メンバーにのみ表示されます)

Databricks-Certified-Professional-Data-Engineer試験無料問題集「Databricks Certified Professional Data Engineer 認定」