hive mapreduce

Hive is a data warehousing tool that allows users to process and analyze large datasets stored in Hadoop Distributed File System (HDFS) using SQL-like queries. Hive uses MapReduce as the underlying processing engine for its queries.

MapReduce is a programming model and software framework used for processing large datasets in parallel across a distributed cluster of nodes. It consists of two phases - Map phase and Reduce phase. The Map phase processes the input data and produces a set of key-value pairs. The Reduce phase takes the output of the Map phase as input and aggregates or summarizes the data based on the keys.

In Hive, when a user submits a query, Hive compiler translates it into a series of MapReduce jobs that are executed on the Hadoop cluster. Hive uses MapReduce to distribute the workload across the cluster and process the data in parallel. Hive also provides a way to write custom MapReduce functions in Java or other programming languages and use them in Hive queries.