Hadoop Trainer Interview Questions and Answers

Bucketing is a technique in Hadoop that groups data into buckets based on a specific column, while partitioning divides data into logical units based on a specific column.

• Bucketing is used to evenly distribute data across multiple files or directories.

• Partitioning is used to organize data based on a specific column, making it easier to query and analyze.

• Bucketing and partitioning can be used together to optimize data storage and query performance.

• For example, in a dataset of ...read more

MapReduce is a programming model used to process large datasets in parallel.

• MapReduce divides the input data into chunks and processes them in parallel.

• Map function processes each chunk and produces intermediate key-value pairs.

• Reduce function aggregates the intermediate results and produces final output.

• MapReduce is used in Hadoop for distributed processing of large datasets.

• Example: Counting the frequency of words in a large text file using MapReduce.