- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Tue, 15 Feb 2005 17:26:36 +0000
- To: Steve Harris <S.W.Harris@ecs.soton.ac.uk>
- CC: "'RDF Data Access Working Group'" <public-rdf-dawg@w3.org>
Steve Harris wrote:
> 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
>
Good point. There is an argument for always requiring {}
ARQ will print parsed queries as fully bracketted and indented.
Eclipse plugin and Emacs mode for SPARQL needed!
Andy
PS <e:companyX> -- ???
Received on Tuesday, 15 February 2005 17:27:05 UTC