Book Image

Pentaho Data Integration Beginner's Guide - Second Edition - Second Edition

By : María Carina Roldán
Book Image

Pentaho Data Integration Beginner's Guide - Second Edition - Second Edition

By: María Carina Roldán

Overview of this book

Capturing, manipulating, cleansing, transferring, and loading data effectively are the prime requirements in every IT organization. Achieving these tasks require people devoted to developing extensive software programs, or investing in ETL or data integration tools that can simplify this work. Pentaho Data Integration is a full-featured open source ETL solution that allows you to meet these requirements. Pentaho Data Integration has an intuitive, graphical, drag-and-drop design environment and its ETL capabilities are powerful. However, getting started with Pentaho Data Integration can be difficult or confusing. "Pentaho Data Integration Beginner's Guide - Second Edition" provides the guidance needed to overcome that difficulty, covering all the possible key features of Pentaho Data Integration. "Pentaho Data Integration Beginner's Guide - Second Edition" starts with the installation of Pentaho Data Integration software and then moves on to cover all the key Pentaho Data Integration concepts. Each chapter introduces new features, allowing you to gradually get involved with the tool. First, you will learn to do all kinds of data manipulation and work with plain files. Then, the book gives you a primer on databases and teaches you how to work with databases inside Pentaho Data Integration. Moreover, you will be introduced to data warehouse concepts and you will learn how to load data in a data warehouse. After that, you will learn to implement simple and complex processes. Finally, you will have the opportunity of applying and reinforcing all the learned concepts through the implementation of a simple datamart. With "Pentaho Data Integration Beginner's Guide - Second Edition", you will learn everything you need to know in order to meet your data manipulation requirements.
Table of Contents (26 chapters)
Pentaho Data Integration Beginner's Guide
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Best Practices
Index

Time for action – using a Database lookup step to create a list of products to buy


Suppose that you have an online system for your customers to order products. On a daily basis, the system creates a file with the orders information. Now, you will check if you have stock for the ordered products and make a list of the products you'll have to buy:

  1. Create a new transformation.

  2. From the Input category of steps, drag a Get data from XML step to the canvas.

  3. Use it to read the orders.xml file. In the Content tab, fill the Loop XPath option with the /orders/order string. In the Fields tab, get the fields. Also, as the first row insert an integer field named ordernumber. This is an attribute in the file, so as Xpath, type @ordernumber.

  4. Do a preview. You will see the following:

    Note

    To keep this exercise simple, the file contains a single product by order.

  5. Add a Sort rows step, and use it to sort the data by man_code and prod_code.

  6. Add a Group by step and double-click on it.

  7. Use the upper grid for grouping...