Hitachi Energy Data Engineer Interview Questions and Answers

ADF is a cloud-based data integration service while Synapse is an analytics service that brings together big data and data warehousing.

• ADF is used for data integration and orchestration tasks, while Synapse is used for big data analytics and data warehousing

• ADF allows you to create data pipelines to move and transform data, while Synapse provides a unified experience for data preparation, data management, data warehous...read more

RDD stands for Resilient Distributed Dataset, a fundamental data structure in Apache Spark.

• RDD is a fault-tolerant collection of elements that can be operated on in parallel.

• RDDs are immutable, meaning they cannot be changed once created.

• RDDs support two types of operations: transformations (creating a new RDD from an existing one) and actions (returning a value to the driver program).

SCD1 and SCD2 are types of slowly changing dimensions used in data warehousing.

• SCD1 (Type 1): Overwrites old data with new data, losing historical information.

• SCD2 (Type 2): Keeps track of historical data by creating new records for changes.

• SCD1 is simpler and faster, while SCD2 provides more detailed historical information.

• Example: SCD1 would update a customer's address directly, while SCD2 would create a new record w...read more