The MRM XML physical format generally respects all of the setting in the logical model, but shares certain restrictions in common with the other physical formats. These restrictions are documented in MRM restrictions.
The MRM XML physical format ignores default and fixed values on elements and attributes. If validation is enabled in WebSphere Message Broker, this can lead to unexpected validation errors for missing elements, even though they have default or fixed values.
The XML properties of an element or attribute of a simple type that is a union or list vary depending on the members of the union or the itemType of the list. If the union or list includes a dateTime type (or other date/time related type) the Date Format field will be displayed. If the union includes a binary type, the Encoding field will be displayed.
The logical properties Min Occurs and Max Occurs specify the permitted number of occurrences of an element or group in a message. They are used when parsing and writing messages, and when validating the content of a message.
When parsing and writing, using the MRM XML physical format, Min Occurs and Max Occurs are effectively ignored. When parsing, the number of occurrences is identified by the tags in the message. When writing, the writer outputs all occurrences in the message tree.
When validating, Min Occurs and Max Occurs are both used to check that the content of the message tree matches the model.