The occurrence data within a room is always unique to a specific item and is not derived from the template. In other words, occurrence data cannot be inherited from the template itself. This implies that even if two rooms share the same item list based on a room template, the individual occurrences in each room can possess different values, such as color or quantity.
There are various scenarios where this uniqueness can be advantageous, although it requires a trade-off between storing data at the occurrence level versus storing it at the item (type) level. Occurrence data can be employed to accommodate minor variations that should not impact the room templates, or when a property is more relevant to the "where" aspect rather than the "how" aspect. For instance, the color of an item may vary depending on the floor level, while the quantity of each item type remains the same. If occurrence data is utilized, relying on templates to update each record becomes unfeasible.
Data that can be stored at the Occurrence level includes:
Quantity - how many times is the Items to be included in the room. The row of Item types would be a single Occurrence with a quantity of instances of that type.
Existing Quantity - If any of the Item types already exists so that procurement is not necessary, this can be specified here. This quantity will then be deducted from the net accounts for this Item.
Priority - Priority for how important the Item Occurrence is compared to other item Occurrences in other Rooms.
Owner - If one or more parties own the Item Occurrence, the party to be specified as Owner of the Item Occurrence can be defined here.
Occurrence Data - Project defined data fields. See next section
The quantity of each Item forms the basis for the gross quantity of this Item in the room. The net quantity is the quantity minus the existing quantity. In addition, there are sub Item which are not to be included in the quantity calculation and deducted so that they are not part of the net quantity. Net quantity together with the Item budget price provides an estimate of how much an Item list for a room will cost. This total figure will be presented in budget reports and reports on Item in room.
Add additional properties
In addition to "core" properties it is possible to create project specific occurrence properties. This can be anything from numbers needed in the project to the color of a chair.
For detailed instructions on creating new properties using a dynamic graphical user interface (GUI) and controlling which item the property is displayed on (Item view filter), look at the admin guide Item Occurrence GUI
Updating Occurrences data
When modifying multiple occurrences, it is possible to update custom occurrence data. However, it is important to note that only properties common to all occurrences can be changed.