- From: Steve Harris <S.W.Harris@ecs.soton.ac.uk>
- Date: Tue, 15 Feb 2005 17:12:47 +0000
- To: "'RDF Data Access Working Group'" <public-rdf-dawg@w3.org>
On Tue, Feb 15, 2005 at 05:02:26PM +0000, Andy Seaborne wrote:
> 3/ Just OPTIONAL, not []
>
> (note that OPTIONAL can take a {} pattern or a plain triple pattern -
> restricting to just {} would be OK).
Quick predication: this reminds me of the popular C typo relating if to
blocks, ie. the difference between
SELECT ?name ?email ?phone
WHERE (?x e:worksFor <e:companyX>)
OPTIONAL{(?x e:emailAddress ?email)
(?x e:phoneNumber ?phone)}
and
SELECT ?name ?email ?phone
WHERE (?x e:worksFor <e:companyX>)
OPTIONAL (?x e:emailAddress ?email)
(?x e:phoneNumber ?phone)
I suspect it will catch people out the same way. Not a huge problem though.
- Steve
Received on Tuesday, 15 February 2005 17:12:52 UTC