June 2009
Intermediate to advanced
524 pages
16h 12m
English
Content preview from Hadoop: The Definitive GuideBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 12. HBase
HBasics
HBase is a distributed column-oriented database built on top of HDFS. HBase is the Hadoop application to use when you require real-time read/write random-access to very large datasets.
Although there are countless strategies and implementations for database storage and retrieval, most solutions—especially those of the relational variety—are not built with very large scale and distribution in mind. Many vendors offer replication and partitioning solutions to grow the database beyond the confines of a single node but these add-ons are generally an afterthought and are complicated to install and maintain. They also come at some severe compromise to the RDBMS feature set. Joins, complex queries, triggers, views, and foreign-key constraints become prohibitively expensive to run on a scaled RDBMS or do not work at all.
HBase comes at the scaling problem from the opposite direction. It is built from the ground-up to scale linearly just by adding nodes. HBase is not relational and does not support SQL, but given the proper problem space it is able to do what an RDBMS cannot: ably host very large, sparsely populated tables on clusters made from commodity hardware.
The canonical HBase use case is the webtable, a table of crawled web pages and their attributes (such as language and MIME type) keyed by the web page URL. The webtable is large with row counts that run into the billions. Batch analytic and parsing MapReduce jobs are continuously ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.