Your first task will be to classify the items into some kind of logical grouping. This could be done manually by sorting and perusing various columns then making a guess as to which is the most efficient grouping. However, if you don't fancy doing that then you can get the DE to do it for you. Click the Drilldown button on the main toolbar.
This will split the bottom half of the main window into two zones, the Tree zone and the View zone.:
Because this is the first time you have used the DE it will automatically invoke the Classifier. The Classifier examines your data and constructs a view based on the optimal grouping. In this case the Classifier has used the aptly named 'Main Group' field from the original data as the main classification group.
Note that the right-hand panel also has a field showing a count of book titles for each group and for the whole database. These type of fields are know as Aggregate fields. We will examine them in more detail later.
The left-hand zone contains a tree-based view of the data shown in the right-hand zone. We will now take a closer look at the Tree.