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Re: SPARQL 1.1 - LeftJoin definition

From: David McNeil <dmcneil@revelytix.com>
Date: Mon, 28 Nov 2011 11:20:26 -0600
Message-ID: <CA+8VvdwBxc1WXHPeiC0C31_TgKnHASmAc1gj8DjWONqX1sKL-g@mail.gmail.com>
To: "Eric Prud'hommeaux" <eric@w3.org>
Cc: public-rdf-dawg-comments@w3.org
Eric - Thanks for the responses, that is helpful. I have another comment
below.

On Mon, Nov 28, 2011 at 11:10 AM, Eric Prud'hommeaux <eric@w3.org> wrote:

> > 4) Given that definition, can't the Filter be pushed down below the
> > LeftJoin? In this way LeftJoin could be simplified because it would no
> > longer need to take an expression.
>
> If I understand, that would remove compatible rows with failed
> filters, as opposed to retaining the row on the left side of the
> optional.
>

The way I am thinking of  it since it is a LeftJoin, the compatible rows
with failed filters would be removed from the right side, but since it is a
LeftJoin, the rows on the left would be retained (since that is what a
LeftJoin does).

-David
Received on Monday, 28 November 2011 17:21:02 GMT

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