- From: Pat Hayes <phayes@ihmc.us>
- Date: Mon, 10 Jul 2017 09:08:59 -0700
- To: Florian Kleedorfer <florian.kleedorfer@austria.fm>
- Cc: Graham Klyne <gk@ninebynine.org>, Simon.Cox@csiro.au, semantic-web@w3.org
> On Jul 10, 2017, at 6:52 AM, Florian Kleedorfer <florian.kleedorfer@austria.fm> wrote: > > > … > I think we have all been talking about the same thing all along: > 1. RDF graphs are sets of triples. Sets are different if their contents differ, there is no notion of mutability of sets. (That was Pat Hayes' point) > 2. RDF graph containers, such as RDF datasets or Graph Stores can be mutable. > 3. RDF graph containers may assign names to RDF graphs. > It follows that an update operation on graph X in the RDF graph container causes a new, different RDF graph to be associated with the name X, which is derived from the old RDF graph by applying the update operation. Or, you can say that it is the container that is named, and this naming is ‘cooler’ as it does not change with time. But then you might want to introduce some way to refer to the contents of the container *at a given time*. > > In short: RDF graphs are always immutable. Over time, graph stores may return different RDF graphs for the same name. Just like a variable can take different values. It is obviously not the value that changes (a 4 does not become a 5), but the variable is assigned a new value. I will try to keep that in mind. :-) Sorry to be so pedantic, but believe me, being careless here can cause many problems downstream. Best wishes Pat > > > 1. https://www.w3.org/TR/2013/REC-sparql11-update-20130321/#graphUpdate > 2. https://www.w3.org/TR/2013/REC-sparql11-update-20130321/#def_graphstore > https://www.w3.org/TR/2013/REC-sparql11-update-20130321/#def_updateoperation > >
Received on Monday, 10 July 2017 16:09:42 UTC