Database model was modified in the previous user interface by the ribbon items of Model-tab. Model-tab was restricted to specific user roles only.
Item Breakdown and split rules was present on input form pages, too, and this remains.
The renewed user interface collects pages to manage database model under Administration menu. This menu and its content is controlled by user roles and might not be visible.
Item Breakdown and split rules is renamed and relocated. In the new interface this item is Breakdown rules and it can be found inside of Data menu. This change is made to simplify menu structures. All users with data modify rights can add their own breakdown rules, but they rarely have access to Administration menu. Data menu is available always and therefore we decided to locate this item here.