Element occurrence compatibility

In the definition of a document as stored in the Data Catalog, the occurrence of elements is specified:

  • An element can be single-occurrence it occurs once, or an element is multi-occurrence and is repeated multiple times. For example, an order header occurs once for each order document, an order line can occur multiple times in a single order document.
  • An element can be optional. It does not have to be included, or an element is mandatory and is required if its parent element exists. For example, inside the DocumentID element, the ID child element is mandatory, while the RevisionID is optional.

The occurrence of an element is displayed behind the element name in the source and target trees. For example:

  • [0..1] means the element is optional, indicated by the ‘0’, and single-occurrence, indicated by the ‘1’.
  • [1..∞] means the element is mandatory, indicated by the ‘1’, and multi-occurrence, indicated by the ∞ sign.
  • If nothing is displayed behind the element name, the element occurs exactly once.

This table shows to what extent you can map elements having a difference in occurrence.

Source element Target Element Notes
Single occurrence Multi-occurrence This mapping can be done.
Multi-occurrence Single occurrence If Allow Mapping Multi-Occurrence Elements to Single-Occurrence Elements is off, this mapping cannot be done.

If Allow Mapping Multi-Occurrence Elements to Single-Occurrence Elements is on, this mapping can be done. In that case, and the source document contains multiple occurrences of the element, only the first occurrence is used. The others are ignored.
Mandatory Optional This mapping can be done.
Optional Mandatory If Allow Mapping Optional Elements to Mandatory Elements is off, this mapping cannot be done.

If Allow Mapping Optional Elements to Mandatory Elements is on, this mapping can be done.

Note: If the source document does not contain the element, the target document also does not contain the element. In that case the resulting document does not match the definition. Use this option only if you are sure that the documents for which the mapping is used contain the source element. This is not uncommon, because in standard BOD definitions most elements are optional.