The Classification Tree is used to control what appears in the right-hand zone (which will now be referred to as the View).
Click the + next to the 'Nonfiction' branch of the tree to open up the next level of categorisation.
We are now beginning to see more detail of what comprises each main group along with aggregates for each sub-group.
We can include and exclude groups from the View by clicking the tick-boxes. Click the tick-box next to 'Fiction' to exclude it from the view. Note that the aggregate count for BOOKSHOP#BOOK has now been re-calculated.
The names of the group levels in the Tree are shown in the View's header. We can see that the first level is the 'Main Group' and the second level is 'Main Classifications'.
You may have noticed that the parent groups in the Tree are always above their children o branches (computer people always like to mix their metaphors), whereas the View shows the parent groups below the children. This is because the View is currently showing aggregates, which summarise group features and so, naturaly, are placed at the end of each group.
View and Tree zones work together, and changes in one affect the other. We will now look at the View zone.