As the name suggests, PySpark is an integration of Apache Spark and the Python programming language. Apache Spark is a widely used open-source framework that is used for cluster-computing and is developed to provide an easy-to-use and faster experience. Python is a high-level general-purpose programming language. It is mainly used for Data Science, Machine Learning and Real-Time Streaming Analytics, apart from its many other uses.
Originally, Apache spark is written in the Scala programming language, and PySpark is actually the Python API for Apache Spark. In this article, we will take a glance at the most frequently asked PySpark interview questions and their answers to help you get prepared for your next interview.
PySpark Interview Questions and Answers
1. What is PySpark?
PySpark is the Python API for Spark. It is used to provide collaboration between Spark and Python. PySpark focuses on processing structured and semi-structured data sets and also provides the facility to read data from multiple sources which have different data formats. Along with these features, we can also interface with RDDs (Resilient Distributed Datasets ) using PySpark. All these features are implemented using the py4j library.
2. List the advantages and disadvantages of PySpark? (Frequently asked PySpark Interview Question)
The advantages of using PySpark are:
- Using the PySpark, we can write a parallelized code in a very simple way.
- All the nodes and networks are abstracted.
- PySpark handles all the errors as well as synchronization errors.
- PySpark contains many useful in-built algorithms.
The disadvantages of using PySpark are:
- PySpark can often make it difficult to express problems in MapReduce fashion.
- When compared with other programming languages, PySpark is not efficient.
3. What are the various algorithms supported in PySpark?
The different algorithms supported by PySpark are:
4. What is PySpark SparkContext?
PySpark SparkContext can be seen as the initial point for entering and using any Spark functionality. The SparkContext uses py4j library to launch the JVM, and then create the JavaSparkContext. By default, the SparkContext is available as ‘sc’.
5. What is PySpark SparkFiles?
PySpark SparkFiles is used to load our files on the Apache Spark application. It is one of the functions under SparkContext and can be called using sc.addFile to load the files on the Apache Spark. SparkFIles can also be used to get the path using SparkFile.get or resolve the paths to files that were added from sc.addFile. The class methods present in the SparkFiles directory are getrootdirectory() and get(filename).
Read: Spark Project Ideas
6. What is PySpark SparkConf?
PySpark SparkConf is mainly used to set the configurations and the parameters when we want to run the application on the local or the cluster.
We run the following code whenever we want to run SparkConf:
localdefaults = True,
_jvm = None,
_jconf = None
7. What is PySpark StorageLevel?
PySpark StorageLevel is used to control how the RDD is stored, take decisions on where the RDD will be stored (on memory or over the disk or both), and whether we need to replicate the RDD partitions or to serialize the RDD. The code for StorageLevel is as follows:
class pyspark.StorageLevel( useDisk, useMemory, useOfHeap, deserialized, replication = 1)
8. What is PySpark SparkJobinfo?
PySpark SparkJobinfo is used to gain information about the SparkJobs that are in execution. The code for using the SparkJobInfo is as follows:
class SparkJobInfo(namedtuple(“SparkJobInfo”, “jobId stageIds status ”)):
9. What is PySpark SparkStageinfo?
PySpark SparkStageInfo is used to gain information about the SparkStages that are present at that time. The code used fo SparkStageInfo is as follows:
class SparkStageInfo(namedtuple(“SparkStageInfo”, “stageId currentAttemptId name numTasks unumActiveTasks” “numCompletedTasks numFailedTasks” )):
Also Read: Apache Spark Developer Salary in India
We hope you went through all the frequently asked PySpark Interview Questions. Apache Spark is mainly used to handle BigData and is in very high demand as companies move forward to use the latest technologies to drive their businesses. If you wish to learn BigData in detail and on an industry level, upGrad provides you with an opportunity to join their PG Diploma in Software Development with Specialisation in Big Data. Do check out his course in order to learn from the best academicians and industry leaders to upgrade your career in this field.