(could have been: Primary and Foreign Keys)
I'm trying to work out som PK/FK mappings to key/keyref structures.
The spec says that the selector must involve the child axis. This imples that in the following example:
<file> . . . etc
I would not be able to specify a unique or key for <file> consisting of the combination of <directoryid> & <fileid>, since the selector must point to either one or the other of these, unless the key is specified in the parent <files>.
Anyone know if this is correct? It seems a bit limiting since I can't then reuse that constraint in other contexts where <file> is used without redefining it.