Databricks Databricks-Certified-Associate-Developer-for-Apache-Spark-3.0 Quiz 1 Topic 2 Questions 1-5

Question: 1

Which of the following code blocks generally causes a great amount of network traffic?

ADataFrame.select()

BDataFrame.coalesce()

CDataFrame.collect()

DDataFrame.rdd.map()

EDataFrame.count()

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Question: 2

Which of the following describes a way for resizing a DataFrame from 16 to 8 partitions in the most efficient way?

AUse operation DataFrame.repartition(8) to shuffle the DataFrame and reduce the number of partitions.

BUse operation DataFrame.coalesce(8) to fully shuffle the DataFrame and reduce the number of partitions.

CUse a narrow transformation to reduce the number of partitions.

DUse a wide transformation to reduce the number of partitions.
Use operation DataFrame.coalesce(0.5) to halve the number of partitions in the DataFrame.

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Question: 3

In which order should the code blocks shown below be run in order to read a JSON file from location jsonPath into a DataFrame and return only the rows that do not have value 3 in column

productId?

1. importedDf.createOrReplaceTempView("importedDf")

2. spark.sql("SELECT * FROM importedDf WHERE productId != 3")

3. spark.sql("FILTER * FROM importedDf WHERE productId != 3")

4. importedDf = spark.read.option("format", "json").path(jsonPath)

5. importedDf = spark.read.json(jsonPath)

A4, 1, 2

B5, 1, 3

C5, 2

D4, 1, 3

E5, 1, 2

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Question: 4

Which of the following statements about Spark's execution hierarchy is correct?

AIn Spark's execution hierarchy, a job may reach over multiple stage boundaries.

BIn Spark's execution hierarchy, manifests are one layer above jobs.

CIn Spark's execution hierarchy, a stage comprises multiple jobs.

DIn Spark's execution hierarchy, executors are the smallest unit.

EIn Spark's execution hierarchy, tasks are one layer above slots.

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Question: 5

Which of the following statements about lazy evaluation is incorrect?

APredicate pushdown is a feature resulting from lazy evaluation.

BExecution is triggered by transformations.

CSpark will fail a job only during execution, but not during definition.

DAccumulators do not change the lazy evaluation model of Spark.

ELineages allow Spark to coalesce transformations into stages

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Databricks Databricks-Certified-Associate-Developer-for-Apache-Spark-3.0 Quiz:1 Topic:2 Questions:1-5