Book Image

QlikView for Developers Cookbook

By : Stephen Redmond
Book Image

QlikView for Developers Cookbook

By: Stephen Redmond

Overview of this book

QlikView has been around since 1993, but has only really taken off in recent years as a leader in the in-memory BI space and, more recently, in the data discovery area. QlikView features the ability to consolidate relevant data from multiple sources into a single application, as well as an associative data model to allow you to explore the data to a way your brain works, state-of-the-art visualizations, dashboard, analysis and reports, and mobile data access. QlikView for Developers Cookbook builds on your initial training and experiences with QlikView to help you become a better developer. This book features plenty of hands-on examples of many challenging functions. Assuming a basic understanding of QlikView development, this book provides a range of step-by-step exercises to teach you different subjects to help build your QlikView developer expertise. From advanced charting and layout to set analysis; from advanced aggregations through to scripting, performance, and security, this book will cover all the areas that you need to know about. The recipes in this book will give you a lot of the information that you need to become an excellent QlikView developer.
Table of Contents (19 chapters)
QlikView for Developers Cookbook
Credits
Foreword
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Replacing IsNull


IsNull is a function that has similarities in many programming languages. It is not always the same though. In QlikView, this function returns a Boolean value of true or false; if the passed value is null.

There is a big "however" here though. Depending upon the version of QlikView that you have, IsNull does not always return what you expect. There are differences between 32-bit and 64-bit versions on how the values are handled. It should also be noted that blank values in text files or inline data will be treated as empty strings rather than null.

SQL Server developers will be familiar with the SQL function of ISNULL (or COALESCE) that, instead of just returning a Boolean value, will return a default value if the passed value is actually null. It can be useful to replicate this.

Getting ready

Load the following script:

Load 
  Country,
  If(IsNull(Sales), 0, Sales) As Sales
Inline [
  Country, Sales
  USA, 1020
  UK, 965
  Germany, 
  France, 890
];

How to do it...

These steps...