Book Image

Apache Hive Cookbook

Book Image

Apache Hive Cookbook

Overview of this book

Hive was developed by Facebook and later open sourced in Apache community. Hive provides SQL like interface to run queries on Big Data frameworks. Hive provides SQL like syntax also called as HiveQL that includes all SQL capabilities like analytical functions which are the need of the hour in today’s Big Data world. This book provides you easy installation steps with different types of metastores supported by Hive. This book has simple and easy to learn recipes for configuring Hive clients and services. You would also learn different Hive optimizations including Partitions and Bucketing. The book also covers the source code explanation of latest Hive version. Hive Query Language is being used by other frameworks including spark. Towards the end you will cover integration of Hive with these frameworks.
Table of Contents (19 chapters)
Apache Hive Cookbook
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface
Index

Partitioning


Partitioning in Hive is used to increase query performance. Hive is very good tool to perform queries on large datasets, especially datasets that require a scan of an entire table. Generally, users are aware of their data domain, and in most of cases they want to search for a particular type of data. For such cases, a simple query takes large time to return the result because it requires the scan of the entire dataset. The concept of partitioning can be used to reduce the cost of querying the data. Partitions are like horizontal slices of data that allows the large sets of data as more manageable chunks.

Table partitioning means dividing the table data into some parts based on the unique values of particular columns (for example, city and country) and segregating the input data records into different files or directories.

Getting ready

This recipe requires Hive installed as described in the Installing Hive recipe of Chapter 1, Developing Hive. You will also need Hive CLI or the...