Book Image

Learning Pentaho Data Integration 8 CE - Third Edition

Book Image

Learning Pentaho Data Integration 8 CE - Third Edition

Overview of this book

Pentaho Data Integration(PDI) is an intuitive and graphical environment packed with drag-and-drop design and powerful Extract-Tranform-Load (ETL) capabilities. This book shows and explains the new interactive features of Spoon, the revamped look and feel, and the newest features of the tool including transformations and jobs Executors and the invaluable Metadata Injection capability. We begin with the installation of PDI software and then move on to cover all the key PDI concepts. Each of the chapter introduces new features, enabling you to gradually get practicing with the tool. First, you will learn to do all kind of data manipulation and work with simple plain files. Then, the book teaches you how you can work with relational databases inside PDI. Moreover, you will be given a primer on data warehouse concepts and you will learn how to load data in a data warehouse. During the course of this book, you will be familiarized with its intuitive, graphical and drag-and-drop design environment. By the end of this book, you will learn everything you need to know in order to meet your data manipulation requirements. Besides, your will be given best practices and advises for designing and deploying your projects.
Table of Contents (17 chapters)

Looking up data in different ways


You already know how to read, insert, update, and delete data from a database. You're ready to learn how to look up data. Let's call lookup as the act of searching information in a database. You can lookup a column of a single table or you can do more complex lookups. In this section, you will learn to perform both the simplest and the more complex kinds of lookups.

Doing simple lookups with the Database Value Lookup step

The Database Value Lookup step allows you to lookup values in a database table based on data you have in your main stream.

The following screenshot shows the Database Value Lookup configuration window, which looks very similar to the Stream lookup step you already know:

Database Value Lookup configuration window

In the upper section, you have the database connection and the table where you will look for data.

Then you have two grids:

  • In the upper grid, you specify the keys to look up.
  • In the lower grid, you put the name of the table columns you...