Big Data Interview Questions and Answers

Big Data is practically implemented in various industries like healthcare, finance, retail, and transportation.

• In healthcare, Big Data is used for analyzing patient data to improve treatment outcomes and develop personalized medicine.

• In finance, Big Data is used for fraud detection, risk analysis, and algorithmic trading.

• In retail, Big Data is used for customer segmentation, demand forecasting, and inventory management.

• In transportation, Big Data is used for optimizing routes...read more

Repartition increases or decreases the number of partitions in a DataFrame, while coalesce only decreases the number of partitions.

• Repartition involves shuffling data across the network, while coalesce tries to minimize shuffling by only creating new partitions if necessary.

• Repartition is typically used when increasing the number of partitions for parallelism, while coalesce is used for decreasing partitions to optimize performance.

• Example: df.repartition(10) vs df.coalesce(5...read more

Spark architecture is a distributed computing framework that consists of a cluster manager and worker nodes.

• Consists of a cluster manager (e.g. Spark Standalone, YARN, Mesos) for resource management

• Worker nodes execute tasks and store data in memory or disk

• Supports various programming languages like Scala, Java, Python, and SQL

• Uses Resilient Distributed Datasets (RDDs) for fault-tolerant distributed data processing

Broadcast join is a type of join operation in big data processing where one of the datasets is small enough to be broadcasted to all nodes in the cluster.

• Used when one dataset is small enough to fit in memory of all nodes

• Reduces shuffling of data across the network

• Improves performance by avoiding data transfer over the network