Book Image

Amazon SimpleDB Developer Guide

Book Image

Amazon SimpleDB Developer Guide

Overview of this book

SimpleDB is a highly scalable, simple-to-use, and inexpensive database in the cloud from Amazon Web Services. But in order to use SimpleDB, you really have to change your mindset. This isn't a traditional relational database; in fact it's not relational at all. For developers who have experience working with relational databases, this may lead to misconceptions as to how SimpleDB works.This practical book aims to address your preconceptions on how SimpleDB will work for you. You will be quickly led through the differences between relational databases and SimpleDB, and the implications of using SimpleDB. Throughout this book, there is an emphasis on demonstrating key concepts with practical examples for Java, PHP, and Python developers.You will be introduced to this massively scalable schema-less key-value data store: what it is, how it works, and why it is such a game-changer. You will then explore the basic functionality offered by SimpleDB including querying, code samples, and a lot more. This book will help you deploy services outside the Amazon cloud and access them from any web host.You will see how SimpleDB gives you the freedom to focus on application development. As you work through this book you will be able to optimize the performance of your applications using parallel operations, caching with memcache, asynchronous operations, and more.
Table of Contents (16 chapters)
Amazon SimpleDB Developer Guide
Credits
Foreword
About the Authors
About the Reviewers
Preface

Queries with Select


Now let us run some simple queries against the data that we imported into the songs domain and get familiar with the syntax. Using one of the three examples discussed, you can create the songs domain in your SimpleDB database. Using either the SDBtool Firefox plugin that was discussed in Chapter 2, Getting Started with SimpleDB, or the PHP Try-SQL-Queries sample program, you can try these SQL queries as well as variations on them.

Comparison operators

Select all attribute/values from songs where the Song attribute is My Way. It is important to note that domains and attributes are case-sensitive.

Enter:

SELECT * FROM songs WHERE Song = 'My Way'

Result:

Item name

Song

Artist

Year

Genre

Rating

112222222

My Way

Frank Sinatra

2002

Easy Listening

**** 4 stars Excellent

The list of available comparison operators includes =, !=, >, >=, <, and<=.

Greater than

Retrieve all songs where the Year is greater than 2000.

Note

In Chapter 4, The SimpleDB Data Model, we...