Special Characters: Occurrence Indicators

The Data View Builder uses a set of special characters (occurrence indicators) to indicate the number of items in a sequence. Occurrence indicators are generally used to specify characteristics for elements or attributes in schemas, but are also found elsewhere in the Builder user interface (UI) where they are needed to specify occurrence characteristics. You can apply these characteristics to elements and attributes of schemas that you build or modify by accessing the right-mouse click pop-up menu on schema nodes.

Table 2-4 Occurrence Indicators in Data View Builder

Character	Description
Question mark (?)	Indicates zero items or one single item. The item is optional and does not have to be included or mapped.
Asterisk (*)	Indicates zero or more items. This item is optional and multiple occurrences of it are allowed.
Plus sign (+)	Indicates one or more items. This is a required element of which multiple occurrences are allowed.