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Re: Hierarchical query

From: Vadim Tropashko <vadimtro_invalid_at_yahoo.com>
Date: Thu, 14 Jun 2007 10:54:31 -0700
Message-ID: <1181843671.368491.185520@a26g2000pre.googlegroups.com>


On Jun 14, 10:35 am, Jan Hidders <hidd..._at_gmail.com> wrote:
> On 14 jun, 18:41, Vadim Tropashko <vadimtro_inva..._at_yahoo.com> wrote:
> > I was going to define tree query in pure language settings, be it
> > regular languges, context free grammars, or else.
>
> ?? How does one query a set of strings in a "pure language setting"?
> Of course you might select certain strings from the set with something
> that accepts strings from a certain language, but that is clearly
> inadequate because you cannot take the "context" of the node into
> account.

And what the node's "context" would be? A set of attributes? If so, then we are in pure relational world. I don't feel comfortable, however, that we use the two completely different mechanics: languges for parsing and building the derivation tree, and relations for querying.

The question is if all these attributes are not redundant and can't be collapsed into a single attribute. Then language approach would become possible. Received on Thu Jun 14 2007 - 12:54:31 CDT

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