[Application-profiles-ig] Cardinality

2019年9月8日03:38:30 BST

All, Hopefully Tom and I will soon be able to provide full minutes of the September 2 meeting about planning for the Hack Day at DCMI 2019. The agenda, which itself is pretty meaty, is here: [1] One question that came up around cardinality was one that I've intended to write up for a while. I'll try to explain it here, but it may help to look at the attached very minimal diagram. The question is about where cardinality belongs in terms of the entities. If you look at the diagram, cardinality is on the relationship between entities, such as between description sets and descriptions, between descriptions and statements. This is exactly where cardinality "resides" in an entity-relation model. Our choice is where to place the cardinality in our vocabulary. It has to be coded in either the "calling" entity or the "called" entity (if that makes sense). Right now we have cardinality in the "called" entities so that the entities cannot be separated from their cardinality. In the recent example that Nishad and I worked on, we decided to place the cardinality on the "calling" entity, which you will see clearly in the YAML file [2], like where the book Description includes the "title" statement with its cardinality: description: - &book descID: book displayName: Book statements: - << : *title minOccur : 1 maxOccur : 1 This says that the description is "calling" or linking two the title and giving that link the cardinality rule of 1,1. Then the title statement itself then does not include cardinality: statement: - &title statementID: title displayName: title value : *value_literal_3_250 The desire is to increase usability of the entities, but in fact it may turn out to be a good solution in some instances, but not in others. This is something we can try out during the Hack Day. kc [1]https://hackmd.io/QBn-xdKjSvyytYt3yJIpzA?both#DCAP2[2]https://github.com/dcmi/dcap/blob/master/examples/bookCaseEG.yaml——Karen Coylekcoyleat kcoyle.nethttp://kcoyle.netskype: kcoylenet -- Karen Coylekcoyleat kcoyle.nethttp://kcoyle.netskype: kcoylenet -------------- next part -------------- A non-text attachment was scrubbed... Name: dspMinimal.png Type: image/png Size: 9909 bytes Desc: not available URL: <https://lists.www.voudr.com/pipermail/application-profiles-ig/attachments/20190907/1797c812/attachment.png>