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

Moving part of a transformation to a subtransformation


Suppose that you have a part of a transformation that you would like to use in another transformation. A quick way to do that would be to copy the set of steps and paste them into the other transformation, and then perform some modifications, for example, changing the names of the fields accordingly. Now you realize that you need it in a third place. You do that again: copy, paste, and modify.

What if you notice that there was a bug in that part of the transformation? Or maybe you'd like to optimize something there? You would need to do that in three different places! This inconvenience is one of the reasons why you might like to move those steps to a common place—a subtransformation.

In this recipe, you will develop a subtransformation that receives the following two dates:

  • A date of birth

  • A reference date

The subtransformation will calculate how old a person was (or will be) at the reference date if the date of birth provided was theirs...