Databases Reference
In-Depth Information
Basic Data Transformation
At this point in the topic, we've already covered topics related to data sources such
as extraction, data visualization, scripting, and data modeling. These topics are all
interconnected in the development process. We will now complement these four
topics with a fifth subject that is of fundamental importance, and one that plays
an essential role when developing QlikView apps, taking to an advanced level the
lessons learned from all of the previous chapters:
Data Transformation
.
The topics we'll cover here will help us:
• Make the data sources adequate to meet our data model design requirements
• Deal with unstructured tables (such as Crosstables) and incorporate them
into our data model
On we go.
Changing the source table structure
We've seen how the QlikView engine works and the importance of having a data
model design that fully takes advantage of QlikView's associative algorithms. So,
the first section of this chapter deals with
transforming
source tables to make them
adequate for our data model. The different structure transformations we'll make are:
• "Cleansing" a dirty table
• Converting a Crosstable to a standard table
• Using hierarchy tables
• Loading generic tables
