Book Image

Pentaho Data Integration Cookbook - Second Edition - Second Edition

Book Image

Pentaho Data Integration Cookbook - Second Edition - Second Edition

Overview of this book

Pentaho Data Integration is the premier open source ETL tool, providing easy, fast, and effective ways to move and transform data. While PDI is relatively easy to pick up, it can take time to learn the best practices so you can design your transformations to process data faster and more efficiently. If you are looking for clear and practical recipes that will advance your skills in Kettle, then this is the book for you. Pentaho Data Integration Cookbook Second Edition guides you through the features of explains the Kettle features in detail and provides easy to follow recipes on file management and databases that can throw a curve ball to even the most experienced developers. Pentaho Data Integration Cookbook Second Edition provides updates to the material covered in the first edition as well as new recipes that show you how to use some of the key features of PDI that have been released since the publication of the first edition. You will learn how to work with various data sources – from relational and NoSQL databases, flat files, XML files, and more. The book will also cover best practices that you can take advantage of immediately within your own solutions, like building reusable code, data quality, and plugins that can add even more functionality. Pentaho Data Integration Cookbook Second Edition will provide you with the recipes that cover the common pitfalls that even seasoned developers can find themselves facing. You will also learn how to use various data sources in Kettle as well as advanced features.
Table of Contents (21 chapters)
Pentaho Data Integration Cookbook Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
References
Index

Comparing two streams and generating differences


Suppose that you have two streams with the same structure and want to find out the differences in the data. Kettle has a step meant specifically for that purpose: the Merge Rows (diff) step. In this recipe, you will see how it works.

Suppose that you have a file with information about the fastest roller coasters around the world. Now, you get an updated file and want to find out the differences between the files: there can be new roller coasters in the list; maybe some roller coasters are no longer among the fastest. Besides, you were told that in the old file, there were some errors about the location, country, and year information, so you are also interested in knowing if some of these have changed.

Getting ready

For this recipe, you will need two files with information about roller coasters. You can download them from the book's site.

Both files have the same structure and look like the following:

Roller_Coaster|Speed|park|location|country|Year...