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Proposal to drop disjunction requirement

From: Steve Harris <S.W.Harris@ecs.soton.ac.uk>
Date: Thu, 30 Sep 2004 14:01:50 +0100
To: DAWG public list <public-rdf-dawg@w3.org>
Message-ID: <20040930130150.GD23464@login.ecs.soton.ac.uk>

In order to close the disjunction issue, I propose that we drop any
requirement for graph disjunction in this version of the query language.

For those who we're at the Bristol F2F, a quick summary of why I don't
like disjunction:

OR is the only infix operator we have prposed so far, so it complicates
the syntax from the point of view of learning it, and makes the precidence
rules more complex and requires logical ()'s to scope expressions.

Disjuntion provides a lot of the same capability as optional matches, but
as a developer I've only seen feature reqests expressed in terms of
optional match, no disjunction. Many disjunctive queries can be expressed
in terms of optionals and value disjunctions, but I have not attempted to
show wether all can be or not.

Getting good coverage for test cases will be hard. Esspecially in
combination with optional it allows you to write some really complex
expressions. Testing all combinations will be difficult.

- Steve
Received on Thursday, 30 September 2004 13:01:55 GMT

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