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If you're interested in the differences between the object model of Fedora 3 and earlier and the object model of Fedora 4, start here.
(Cribbed heavily from the JCR Repository Model documentation)
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Nodes can have zero or more child nodes. Nodes can have zero or more properties. Properties can hold one or more values. Fedora doesn't currently support blank nodes.
The location of an item in the workspace graph can be described by the path from the root node to that item. The path consists of the name of each interceding node in order from root to target item, much like a file system path.
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