Book Image

Learning HBase

By : Shashwat Shriparv
Book Image

Learning HBase

By: Shashwat Shriparv

Overview of this book

Table of Contents (18 chapters)
Learning HBase
Credits
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Index

Data types in HBase


There are no fancy data types such as String, INT, or Long in HBase; it's all byte array. It's a kind of byte-in and byte-out database, wherein, when a value is inserted, it is converted into a byte array using the Put and Result interfaces. HBase implicitly converts the data to byte arrays through a serialization framework, stores it into the cell, and also gives out byte arrays. It implicitly converts data to equivalent representation while putting and getting the value.

So, in short, we can say that HBase cells only hold byte arrays. Put and Result methods handle encoding and decoding of objects.

Anything that can be converted into bytes, from a simple string to an image file, can be stored in HBase, but it too is converted into bytes and can then be stored (or as long as it's a serializable object). We can have values up to 10 to 15 MB stored in an HBase cell. If any value is bigger, we need not store it into HBase, what we can do is store the file on HDFS and then...