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Linked Data Patterns (PDF) Linked Data Patterns A pattern catalogue for modelling, publishing, and consuming Linked Data Leigh Dodds Ian Davis Linked Data Patterns: A pattern catalogue for modelling, publishing, and consuming Linked Data Leigh Dodds Ian Davis Publication date 2012-05-31 Abstract This book lives at http://patterns.dataincubator.org. Check that website for the latest version. The book is also available as both a PDF [http://patterns.dataincubator.org/book/linked-data-patterns.pdf] and EPUB [http://patterns.dataincubator.org/book/linked-data-patterns.epub] download. This work is licenced under the Creative Commons Attribution 2.0 UK: England & Wales License. To view a copy of this licence, visit http://creativecommons.org/licenses/by/2.0/uk/. Thanks to members of the Linked Data mailing list [http://lists.w3.org/Archives/Public/public-lod/] for their feedback and input, and Sean Hannan [http://twitter.com/MrDys/] for contributing some CSS to style the online book. Table of Contents 1. Introduction ................................................................................................................... 1 Overview .................................................................................................................. 1 2. Identifier Patterns ............................................................................................................ 4 Hierarchical URIs ....................................................................................................... 4 Literal Keys .............................................................................................................. 5 Natural Keys ............................................................................................................. 6 Patterned URIs ........................................................................................................... 6 Proxy URIs ............................................................................................................... 7 Rebased URI ............................................................................................................. 8 Shared Keys .............................................................................................................. 9 URL Slug ................................................................................................................ 10 3. Modelling Patterns ........................................................................................................ 12 Custom Datatype ...................................................................................................... 13 Index Resources ....................................................................................................... 14 Label Everything ...................................................................................................... 15 Link Not Label ......................................................................................................... 16 Multi-Lingual Literal ................................................................................................. 18 N-Ary Relation ......................................................................................................... 19 Ordered List ............................................................................................................ 20 Ordering Relation ..................................................................................................... 21 Preferred Label ......................................................................................................... 22 Qualified Relation ..................................................................................................... 23 Reified Statement ..................................................................................................... 25 Repeated Property ..................................................................................................... 26 Topic Relation .......................................................................................................... 27 Typed Literal ........................................................................................................... 28 4. Publishing Patterns ........................................................................................................ 30 Annotation ............................................................................................................... 30 Autodiscovery .......................................................................................................... 31 Dataset Autodiscovery ............................................................................................... 32 Document Type ........................................................................................................ 33 Edit Trail ................................................................................................................ 34 Embedded Metadata .................................................................................................. 35 Equivalence Links ..................................................................................................... 36 Link Base ................................................................................................................ 37 Materialize Inferences ................................................................................................ 38 Primary Topic Autodiscovery ...................................................................................... 39 Progressive Enrichment .............................................................................................. 40 See Also ................................................................................................................. 41 Unpublish ................................................................................................................ 41 5. Data Management Patterns .............................................................................................. 44 Graph Annotation ..................................................................................................... 44 Graph Per Aspect ..................................................................................................... 47 Graph Per Resource .................................................................................................. 49 Graph Per Source ..................................................................................................... 51 Named Graph ........................................................................................................... 53 Union Graph ............................................................................................................ 54 6. Application Patterns ....................................................................................................... 57 Assertion Query ........................................................................................................ 57 Blackboard .............................................................................................................. 58 Bounded Description ................................................................................................. 59 iii Linked Data Patterns Composite Descriptions ............................................................................................. 60 Follow Your Nose .................................................................................................... 61 Missing Isn't Broken ................................................................................................. 62 Named Query ........................................................................................................... 64 Parallel Loading ....................................................................................................... 65 Parallel Retrieval ...................................................................................................... 66 Parameterised Query ................................................................................................. 66 Resource Caching ..................................................................................................... 68 Schema Annotation ................................................................................................... 68 Smushing ................................................................................................................ 69 Transformation Query ................................................................................................ 72 URI Resolver ........................................................................................................... 73 iv Chapter 1. Introduction Abstract There are many ways to help spread the adoption of a technology, and to share skills and experience amongst a community of practitioners. Different approaches work well for communicating different kinds of knowledge. And we all individually have a preferred means of acquiring new skills, or getting help with a specific problem. Reference manuals, tutorials, recipes, best practice guides and experience reports all have their role. As do training courses, mentoring, pair programming and code reviews. This book attempts to add to the steadily growing canon of reference documentation relating to Linked Data. Linked Data is a means of publishing "web-native" data using standards like HTTP, URIs and RDF. The book adopts a tried and
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