- From: Steve Harris <steve.harris@garlik.com>
- Date: Mon, 8 Feb 2010 11:50:19 +0000
- To: Ivan Mikhailov <imikhailov@openlinksw.com>
- Cc: Andy Seaborne <andy.seaborne@talis.com>, SPARQL Working Group <public-rdf-dawg@w3.org>
On 8 Feb 2010, at 11:00, Ivan Mikhailov wrote: > IN should be based on equality. For IN based on SAMETERM, a special > function might be introduced. What special function? SPARQL already has sameTerm: http://www.w3.org/TR/rdf-sparql-query/#func-sameTerm Another reason to base it on sameTerm is optimisation. You can replace FILTER(?x = <uri1> || ?x = <uri2> ...) with a simple disjunctive expression on ?x, but you can't with numeric literals as there are an infinite number of literals that are = to "1"^^xsd:integer, for example. This may not matter in anyone else's engine though, so I didn't bring it up before. > If both scalar subqueries and IN are supported then > ?expn IN (SELECT...) > should also be supported, of course. That's a bit of a leap, and I don't think I agree. - Steve -- Steve Harris, Garlik Limited 2 Sheen Road, Richmond, TW9 1AE, UK +44 20 8973 2465 http://www.garlik.com/ Registered in England and Wales 535 7233 VAT # 849 0517 11 Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD
Received on Monday, 8 February 2010 11:50:51 UTC