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

Creating views


In this recipe, you will learn how to create a view in Hive.

Getting ready

A view is a virtual table that acts as a window to the data for the underlying table commonly known as the base table. It consists of rows and columns but no physical data. So when a view is accessed, the underlying base table is queried for the output.

Note

A base table can also be a view that will have a base table of its own. So if the first view is accessed, then the base table of the second view gives the output for the query.

The general syntax of creating a view is as follows:

CREATE VIEW [IF NOT EXISTS] view_name [(column_name [COMMENT column_comment], ...)]
    [COMMENT view_comment]
    [TBLPROPERTIES (property_name = property_value, ...)]
    AS SELECT ...;

Where:

  • [IF NOT EXISTS]: Is an optional clause. If there is an attempt to create a view that is already present in the database, then an error is thrown. In such cases, the IF NOT EXISTS clause is used, which will ignore the entire statement and...