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

Reloads going missing at each row global variable


When using reload at each row with globalMap Key (as seen in the next screenshot), Talend allows you to cut and paste expressions into the globalMap variable, but when you go out of the tMap component and come back in again, you will see that it hasn't changed.

How to do it...

To get around this, you have one of two options:

  1. Drag the field from an input source. This option is limited, in that the expression will be just the field name, so you cannot apply any other logic to the variable, such as substring or uppercase.

  2. The second (and preferred option) is to edit the expression in the Expression editor tab. This method allows any expression to be coded to ensure that the variable is set correctly, as shown in the next screenshot: