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)

Verifying a connection, running DDL scripts, and doing other useful tasks


When you work with databases, before performing CRUD operations, you may want to run other useful tasks, for example, verify if a database is accessible, clean up some tables before execution, and more. Look at the following sample job:

Sample job that runs some database-related tasks

This job verifies the connectivity with a database connection. If the database is accessible, it creates a table—as soon as the table doesn't exist. After that, it executes a Transformation. If the database is not available, a message is written to the log.

Besides these, there are some other job entries that can be useful for database-related tasks. The following table summarizes them:

Job entry

Purpose

Check Db connections

Verifies the connectivity with one or several databases.

Table exists

Verifies that a specified table exists on a database.

Columns exist in a table

Verifies that one or more columns exist in a database table.

Truncate tables...