An event is something that happens in an application which carries a business value--for example, an item is updated or a batch job has finished. The event data is stored in a "document" and the actual event is the operation on the document. Another way to put it is that the document is the object and the operation is the verb. The event occurs in an application, for example, M3.
An event contains the following data:
Publisher. For example, M3
Document name. For example, OOHEAD (order head in M3)
A list of document elements, each having the following:
Element name. For example, ORSL (order status)
Old element value, if applicable
Operation on the document: Create, Update, Delete, Start, eXit, Fail, reQuest, or Response. The operations are hardcoded, but can easily be extended if needed.
The bold and uppercase letters are the operation characters. In subscription strings the operation is given by its operation character.
The order of the document elements is maintained through Event Hub and Event Analytics.