Structured documents are given a new version record when an element within the document is modified, deleted, or a new element is added to the document.
If you are editing a structured document using an integrated XML editor, when you save or check in the document, each element you changed or added is saved with a new version record, which is applied to the structured document object and to each element that was changed or added. Unchanged elements in the structured document are not saved as a new version, and no version record is created.
For example, if you edit a structured document and add a new element, if the structured document itself is checked in as version 1.5, the new element receives an initial version record of 1.5. Unchanged elements in the structured document do not create a new version record. So elements within a structured document may have differing version records, but the structured document itself will always show the most recent version record.
If you are editing an individual element using the fragment editor, when you check in a change, the element is saved with a new version record. If you view the history of the structured document that contains the changed element, it now shows the version record of the changed element.