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

Loading files into tables


Loading data into a Hive table is one of the variants of inserting data into a Hive table. In this method, the entire file is copied/moved to a directory that corresponds to Hive tables. If the table is partitioned, then data is loaded into partitions one at a time. The general syntax of loading the data into a table is as follows:

LOAD DATA [LOCAL] INPATH 'filepath' [OVERWRITE] INTO TABLE tablename [PARTITION (partcol1=val1, partcol2=val2 ...)]

Where:

  • [LOCAL]: This is an optional clause. If this clause is specified, the preceding command will look for the file in the local filesystem. The command will follow the file path in the local filesystem.

  • FILEPATH: This is the path where files reside either in the local filesystem or HDFS.

  • [OVERWRITE]: Is an optional clause. If this clause is specified, the data in the table or partition is deleted and new data is loaded based on the file path in the statement.

  • tablename: This is the name of the table.

  • [PARTITION (partcol1=val1...