- From: Karen Coyle <kcoyle@kcoyle.net>
- Date: Thu, 15 Jan 2015 07:45:31 -0800
- To: Holger Knublauch <holger@topquadrant.com>, "public-data-shapes-wg@w3.org" <public-data-shapes-wg@w3.org>
Thanks, Holger. As usual, I need to do this "by example" because it's quite likely that my vocabulary differs from that of others here. Use cases: I have data that uses dct:title in various places, and I want to say that wherever it is used it can only be used once for each subject in my data. Here's some data: 1) subjectA dce:creator "Somebody" . subjectA dct:title "Some title" . subjectA bf:subject http://.... . subjectB dce:creator "Someone else" . subjectB dct:title "Another title" . 2) subjectA dce:creator "Somebody" . subjectA dct:title "Some title" . subjectA bf:subject ex:subject1 . subjectB dce:creator "Someone else" . subjectB dct:title "Another title" . subject1 dct:title "A related book" . That's a pretty stupid example, and the data is more sophisticated than that, of course. My questions are: a) because this data does not use rdf:type (unless inferred, and let's say it isn't), does subject "s" constitute a node/graph/shape? b) substitute "skos:prefLabel" here and a rule that skos:prefLabel can occur only once per each "X" (X because I dont know what to call it) - is that the same case? c) is this really a new use case, or a variation on existing ones? kc On 1/11/15 3:14 PM, Holger Knublauch wrote: > Hi Karen, > > thanks for your comment on requirement > > https://www.w3.org/2014/data-shapes/wiki/Requirements#Declarations_of_Property_Min.2FMax_Cardinality > > > in which you ask how to represent a constraint such as "there must be > one instance of classX". While I was responding, I noticed that we did > not yet have a story about "global" constraints that are evaluated > independently from specific instances or classes. I propose to call them > "static constraints" and have added a corresponding requirement: > > https://www.w3.org/2014/data-shapes/wiki/Requirements#Static_Constraints > > Although I am confident that this requirement is important, I had a hard > time finding motivating User Stories in our current catalog. I would > therefore encourage you (or anyone else) to write down your requirement > as a User Story and add a cross-link if you are supportive of the Static > Constraints requirement. > > Thanks > Holger > > > -- Karen Coyle kcoyle@kcoyle.net http://kcoyle.net m: 1-510-435-8234 skype: kcoylenet/+1-510-984-3600
Received on Thursday, 15 January 2015 15:46:01 UTC