Re: XQuery (and XML) vs LISP
From: Jan Hidders <jan.hidders_at_REMOVETHIS.pandora.be>
Date: Tue, 07 Feb 2006 21:17:41 GMT
Message-ID: <V78Gf.242000$mZ6.7684231_at_phobos.telenet-ops.be>
Date: Tue, 07 Feb 2006 21:17:41 GMT
Message-ID: <V78Gf.242000$mZ6.7684231_at_phobos.telenet-ops.be>
Marshall Spight wrote:
>
> I vaguely wonder whether it would be possible to use, or adapt,
> relational techniques for querying nested relations as an alternative
> to either XQuery or pattern matching.
I think the answer is, vaguely, yes. :-) You can think of the tree is a binary relation, and if you want access to all descendants the system could provide conceptually the transitive closure to you (so for the binary table R you could for example use R* as the notation for its transitive closure) and from there you could specify your queries as usual. Most XPath queries would then translatie to simple SELECT-FROM-WHERE queres.
- Jan Hidders