Book Image

Talend Open Studio Cookbook

By : Rick Barton
Book Image

Talend Open Studio Cookbook

By: Rick Barton

Overview of this book

Data integration is a key component of an organization's technical strategy, yet historically the tools have been very expensive. Talend Open Studio is the world's leading open source data integration product and has played a huge part in making open source data integration a popular choice for businesses worldwide.This book is a welcome addition to the small but growing library of Talend Open Studio resources. From working with schemas to creating and validating test data, to scheduling your Talend code, you will get acquainted with the various Talend database handling techniques. Each recipe is designed to provide the key learning point in a short, simple and effective manner.This comprehensive guide provides practical exercises that cover all areas of the Talend development lifecycle including development, testing, debugging and deployment. The book delivers design patterns, hints, tips, and advice in a series of short and focused exercises that can be approached as a reference for more seasoned developers or as a series of useful learning tutorials for the beginner.The book covers the basics in terms of schema usage and mappings, along with dedicated sections that will allow you to get more from tMap, files, databases and XML. Geared towards the whole lifecycle, the Talend Open Studio Cookbook shows readers great ways to handle everyday tasks, and provides an insight into all areas of a development cycle including coding, testing, and debugging of code to provide start-to-finish coverage of the product.
Table of Contents (21 chapters)
Talend Open Studio Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Common Type Conversions
Index

Rewritable lookups using an in-process database


The tHash components are great for storing intermediate data in memory and are very efficient, but do not allow updates. Database tables allow updates, but aren't as efficient when writing and reading data on a row-by-row basis, especially when there are large numbers of rows to be processed.

This recipe shows how we can get the best of both worlds using a feature of the HSQL database that allows us to define databases that only reside in memory for the given process.

Due to this job being fairly complex, there are a few techniques used that can be found in other chapters of the book, but aren't explained in detail in this chapter. In addition, it will aid understanding if we provide a background for this scenario.

Background

In this recipe we are presented with a list of customers with their countries of residence. We wish to cross-reference their residence country with our list of countries held in our MySQL database and:

  • if the country is found...