Check-in/Check-out

This function prevents a document from being edited by more than one person at a time. The intent is to eliminate replication conflicts.

When a document is checked out, the original document is marked 'read only' and a response document is created that is visible only to the person who checked out the document. This person then can edit the response document as needed.

Once the document is checked in, the original document is marked for deletion and edited version is promoted to document level. For a short time, 2 document are visible in the view until the original is actually deleted. At this time, only the edited version can be opened for viewing. The result is that the edited document, in effect, replaces the original.

The edited version can then be checked out for further editing. But once the second version is checked-in, the first version is marked for deletion and the second version is the only document left in the db. The objective, therefore, is to keep only the most recently edited version.