/
index.html
4203 lines (3624 loc) · 279 KB
/
index.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<title>Data Catalog Vocabulary (DCAT) - revised edition</title>
<meta content="text/html; charset=utf-8" http-equiv="content-type" />
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<script class="remove" src="https://www.w3.org/Tools/respec/respec-w3c-common"></script>
<script class="remove" src="config.js"></script>
<script>
// @andrea-perego
function popCrossRefs() {
$('a[href^="#"]').each( function () {
var href = $(this).attr('href');
var id = href.trim().replace('#','');
var text = $(this).text();
if (text.trim().length == 0 && id.length > 0 && ( $(href).hasClass('example') || $(href).hasClass('practicelab') )) {
var label = $('.example:has(#' + id + ') > .example-title, *[id="' + id + '"].example > .example-title, *[id="' + id + '"].illegal-example > .example-title, *[id="' + id + '"].practicelab').text();
if (label.trim().length > 0) {
$(this).text(label);
}
}
} );
}
$(document).ready( function() {
popCrossRefs();
});
// @andrea-perego
</script>
<link rel="stylesheet" type="text/css" href="style.css">
<link rel="stylesheet" type="text/css" href="small.css" media="only all and (max-width: 649px)">
<!-- Local style -->
<style type="text/css">
.disclaimer {font-size:.9em;}
</style>
</head>
<body>
<!-- Disclaimer -->
<aside id="disclaimer" class="disclaimer">
<p>★ <strong>Disclaimer</strong>: The views expressed are purely those of the author and may not in any circumstances be regarded as stating an official position of the European Commission.</p>
</aside>
<section id="abstract">
<p>DCAT is an RDF vocabulary designed to facilitate interoperability between data catalogs published on the Web.
This document defines the schema and provides examples for its use.</p>
<p>DCAT enables a publisher to describe datasets and data services in a catalog using a standard model and vocabulary that facilitates the consumption and aggregation of metadata from multiple catalogs.
This can increase the discoverability of datasets and data services.
It also makes it possible to have a decentralized approach to publishing data catalogs and makes federated search for datasets across catalogs in multiple sites possible using the same query mechanism and structure.
Aggregated DCAT metadata can serve as a manifest file as part of the digital preservation process.</p>
<p style="text-indent: 100px;">The namespace for DCAT terms is <code>http://www.w3.org/ns/dcat#</code></p>
<p style="text-indent: 100px;">The suggested prefix for the DCAT namespace is <code>dcat</code></p>
<p style="text-indent: 100px;">The (revised) DCAT vocabulary is available <a href="https://raw.githubusercontent.com/w3c/dxwg/gh-pages/dcat/rdf/dcat.ttl">here</a>.</p>
</section>
<section id="sotd">
<p>
Since the <a href="https://www.w3.org/TR/2018/WD-vocab-dcat-2-20180508/">First Public Working Draft</a>, the main changes to the DCAT vocabulary have been:</p>
<ul>
<li>addition of a <a href="#Class:Resource"><code>dcat:Resource</code></a> class for representing any asset than can be included in the catalog, this is
now the super-class of <a href="#Class:Dataset"><code>dcat:Dataset</code></a></li>
<li>addition of <a href="#Class:Data_Service"><code>dcat:DataService</code></a>, as a sub-class of <a href="#Class:Resource"><code>dcat:Resource</code></a>, to support cataloguing service end-points providing access to data assets</li>
<li>addition of ways to represent <a href="#bag-of-files">loosely structured catalogs</a>, where there is no distinction between a dataset and its distributions</li>
<li>more details for the ways of representing <a href="#examples-dataset-provenance">dataset provenance</a> and <a href="#quality-information">quality</a></li>
<li>an <a href="#dcat-sdo">alignment</a> between the DCAT vocabulary and the schema.org vocabulary</li>
</ul>
<p>
The detailed differences between the two documents can be seen <a href="https://services.w3.org/htmldiff?doc1=https%3A%2F%2Fwww.w3.org%2FTR%2F2018%2FWD-vocab-dcat-2-20180508%2F&doc2=https%3A%2F%2Fwww.w3.org%2FTR%2F2018%2FWD-vocab-dcat-2-20181011%2F">here</a>.
</p>
<p>
<a href="https://github.com/w3c/dxwg/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aopen+label%3Adcat+">Issues, requirements, and features</a> that have been considered and discussed by the Data eXchange Working Group but have not been addressed due to lack of maturity or consensus are collected in GitHub. Those believed to be a priority for a future release are in the milestone <a href="https://github.com/w3c/dxwg/milestone/15">DCAT Future Priority Work</a>.
</p>
<h3 id="dcat_history">DCAT history</h3>
<p>The original DCAT vocabulary was developed and <a href="http://vocab.deri.ie/dcat">hosted</a> at the Digital Enterprise Research Institute (DERI), then refined by the <a href="http://www.w3.org/egov/">eGov Interest Group</a>, and finally standardized in 2014 [[?VOCAB-DCAT-20140116]] by the <a href="http://www.w3.org/2011/gld/">Government Linked Data (GLD)</a> Working Group.</p>
<p>This revised version of DCAT was developed by the <a href="https://www.w3.org/2017/dxwg/">Dataset Exchange Working Group</a> in response to a new set of Use Cases and Requirements [[?DCAT-UCR]] gathered from peoples' experience with the DCAT vocabulary from the time of the original version, and new applications that were not considered in the first version. A summary of the changes from [[?VOCAB-DCAT-20140116]] can be found at <a href="#changes">Change History</a></p>
<h3 id="external_terms">External terms</h3>
<p>DCAT incorporates terms from pre-existing vocabularies where stable terms with appropriate meanings could be found, such as <a href="http://xmlns.com/foaf/0.1/homepage">foaf:homepage</a> and <a href="http://purl.org/dc/terms/title">dct:title</a>.
Informal summary definitions of the externally-defined terms are included here for convenience, while authoritative definitions are available in the normative references.
Changes to definitions in the references, if any, supersede the summaries given in this specification.
Note that conformance to DCAT (Section 4) concerns usage of only the terms in the DCAT namespace itself, so possible changes to the external definitions will not affect the conformance of DCAT implementations.</p>
<h3 id="please_send_comments">Please send comments</h3>
The Working Group invites publishers to describe their catalogs and datasets with the revised version of DCAT described in this document and to report their implementations following <a href="https://github.com/w3c/dxwg/wiki/DCAT-implementation-evidence">the instruction to reporting DCAT revised implementations</a>. The information gathered through this means will be augmented by further analysis of implementation available on the Web. The Working Group expects to adduce the combined set of evidence when requesting that the Director advance this document to Proposed Recommendation.
</section>
<section id="introduction" class="informative">
<h2>Introduction</h2>
<p>Sharing data resources among different organizations, researchers, governments and citizens requires the provision of metadata.
This is irrespective of the data being open or not.
DCAT is a vocabulary for publishing data catalogs on the Web, which was originally developed in the context of government data catalogs
such as <a href="https://www.data.gov/">data.gov</a> and <a href="https://data.gov.uk">data.gov.uk</a>, but it is also applicable and has been used in other contexts.
<p>
<p>
This revision of DCAT has extended the previous version to support further use cases and requirements [[?DCAT-UCR]].
These include the possibility of cataloguing other data resources in addition to
datasets, such as data services. The revision also supports describing relationships between datasets as well as between
datasets and other catalogued resources. Guidance on how to document licenses and rights statements associated with the catalogued items is provided.
</p>
<p>
DCAT provides RDF classes and properties to allow datasets and data services to be described and included in a catalog.
The use of a standard model and vocabulary facilitates the consumption and aggregation of metadata from multiple catalogs, which can:</p>
<ol>
<li>
increase the discoverability of datasets and data services
</li>
<li>
allow federated search for datasets across catalogs in multiple sites
</li>
</ol>
<p>
Data described in a catalog can come in many formats, ranging from spreadsheets, through XML and RDF to various specialized formats.
DCAT does not make any assumptions about these serialization formats of the datasets but it does
distinguish between the abstract dataset and its different manifestations or distributions.
</p>
<p>
Data is often provided through a service accessed through a form or API which supports selection of an extract, sub-set, or combination of data.
DCAT allows the description of a data access service to be included in a catalog.
</p>
<p>
Complementary vocabularies can be used together with DCAT to provide more detailed format-specific information.
For example, properties from the VoID vocabulary [[?VOID]] can be used within DCAT to express various statistics about a dataset if that dataset is in RDF format.
</p>
<p>
This document does not prescribe any particular method of deploying data catalogs expressed in DCAT.
DCAT information can be presented in many forms including RDF accessible via SPARQL endpoints, embedded in HTML pages as [[?HTML-RDFa]], or serialized as RDF/XML [[?RDF-SYNTAX-GRAMMAR]], [[?N3]], [[?Turtle]], [[?JSON-LD]] or other formats.
Within this document the examples use Turtle because of its readability.
</p>
</section>
<section id="motivation" class="informative"><h2>Motivation for change</h2>
<p>The original Recommendation [[?VOCAB-DCAT-20140116]] published in January 2014 provided the basic framework for describing datasets. It made an important distinction between a <i>dataset</i> as an abstract idea and a <i>distribution</i> as a manifestation of the dataset. Although DCAT has been widely adopted, it has become clear that the original specification lacked a number of essential features that were added either through the mechanism of an application profile, such as the European Commission's DCAT-AP [[?DCAT-AP]], or the development of larger vocabularies that to a greater or lesser extent built upon the base standard, such as the Healthcare and Life Sciences Community Profile [[?HCLS-Dataset]], the Data Tag Suite [[?DATS]] and more. This revision of DCAT has been developed to address the specific shortcomings that have come to light through the experiences of different communities, the aim being to improve interoperability between the outputs of these larger vocabularies.
For example, in this new DCAT version we provide classes, properties and guidance to address <a href="#Dereferenceable-identifiers">identifiers</a>, <a href="#quality-information">dataset quality information</a>, and <a href="#data-citation">data citation</a> issues.</p>
<p>This draft includes re-writing of the specification throughout. Significant changes from the 2014 Recommendation are marked within the text using "Note" sections, as well as being described in the <a href="#changes">Change History</a>.</p>
</section>
<section id="namespaces-1">
<h2 >Namespaces</h2>
<p>The namespace for DCAT is <code>http://www.w3.org/ns/dcat#</code>.
However, note that DCAT makes extensive use of terms from other vocabularies, in particular Dublin Core [[?DCTERMS]].
DCAT defines a minimal set of classes and properties of its own.
A full set of namespaces and prefixes used in this document is shown in the table below.</p>
<table id="namespaces">
<thead><tr><th>Prefix</th><th>Namespace</th></tr></thead>
<tbody>
<tr><td>adms</td><td>https://www.w3.org/ns/adms#</td></tr>
<tr><td>dcat</td><td>http://www.w3.org/ns/dcat#</td></tr>
<tr><td>dct</td><td>http://purl.org/dc/terms/</td></tr>
<tr><td>dctype</td><td>http://purl.org/dc/dcmitype/</td></tr>
<tr><td>dqv</td><td>http://www.w3.org/ns/dqv#</td></tr>
<tr><td>foaf</td><td>http://xmlns.com/foaf/0.1/</td></tr>
<tr><td>owl</td><td>http://www.w3.org/2002/07/owl#</td></tr>
<tr><td>prov</td><td>http://www.w3.org/ns/prov#</td></tr>
<tr><td>rdf</td><td>http://www.w3.org/1999/02/22-rdf-syntax-ns#</td></tr>
<tr><td>rdfs</td><td>http://www.w3.org/2000/01/rdf-schema#</td></tr>
<tr><td>sdo</td><td>https://schema.org/</td></tr>
<tr><td>skos</td><td>http://www.w3.org/2004/02/skos/core#</td></tr>
<tr><td>vcard</td><td>http://www.w3.org/2006/vcard/ns#</td></tr>
<tr><td>xsd</td><td>http://www.w3.org/2001/XMLSchema#</td></tr>
</tbody>
</table>
</section>
<section id="conformance">
<p class="note">Modified from DCAT 2014 [[?VOCAB-DCAT-20140116]]</p>
<p>A data catalog conforms to DCAT if:</p>
<ul>
<li> Access to data is organized into datasets, distributions, and data-services. </li>
<li> An RDF description of the catalog itself and its datasets, distributions, and data-services is available (but the choice of
RDF syntax, access protocol, and access policy are not mandated by this specification).</li>
<li> The contents of all metadata fields that are held in the catalog and that contain data about the catalog itself and its datasets, distributions, and data-services, are included in this RDF description and are expressed using the appropriate classes and properties from DCAT, except where no such class or property exists.</li>
<li> All classes and properties defined in DCAT are used in a way consistent with the semantics declared in this specification.</li>
<li>DCAT-compliant catalogs <em title="MAY" class="rfc2119">MAY</em> include additional non-DCAT metadata fields and additional RDF data in the catalog's RDF description.</li>
</ul>
<p>
A <strong>DCAT profile</strong> is a specification for a data catalog that adds additional constraints to DCAT. A data catalog that conforms to the profile also conforms to DCAT. Additional constraints in a profile <em title="MAY" class="rfc2119">MAY</em> include:
</p>
<ul>
<li> Cardinality constraints, including a minimum set of required metadata fields </li>
<li> Sub-classes and sub-properties of the standard DCAT classes and properties</li>
<li> Classes and properties for additional metadata fields not covered in DCAT</li>
<li> Controlled vocabularies or URI sets as acceptable values for properties</li>
<li> Requirements for specific access mechanisms (RDF syntaxes, protocols) to the catalog's RDF description</li>
</ul>
<!--NoBacklogNorCR p class="issue" data-number="430">
The requirement for a DCAT profile to conform to all of DCAT is under discussion.
</p-->
</section>
<section id="vocabulary-overview" class="informative">
<h2>Vocabulary overview</h2>
<!--
<p class="note">Significantly extended from DCAT 2014 [[?VOCAB-DCAT-20140116]]</p>
-->
<section id="dcat-scope">
<h3>DCAT scope</h3>
<p>DCAT is an RDF vocabulary for representing data catalogs.
DCAT is based around eight main classes:</p>
<ul>
<li>
<a href="#Class:Catalog"><code>dcat:Catalog</code></a> represents a catalog, which is a dataset in which each individual item is a metadata record describing some resource; the scope of <code>dcat:Catalog</code> is collections of metadata about <b>datasets</b> or <b>data services</b>.
</li>
<li>
<a href="#Class:Resource"><code>dcat:Resource</code></a> represents an individual item in a catalog.
This class is not intended to be used directly, but is the parent class of <a href="#Class:Dataset"><code>dcat:Dataset</code></a>, <a href="#Class:Data_Service"><code>dcat:DataService</code></a> and <a href="#Class:Catalog">dcat:Catalog</a>.
Member items in a catalog should be members of one of the sub-classes, or of a sub-class of these, or of a sub-class of <a href="#Class:Resource"><code>dcat:Resource</code></a> defined in a DCAT application profile or other DCAT application.
<a href="#Class:Resource"><code>dcat:Resource</code></a> is effectively an extension point for defining a catalog of any kind of resource.
</li>
<li>
<a href="#Class:Dataset"><code>dcat:Dataset</code></a> represents a dataset in a catalog.
A dataset is a collection of data, published or curated by a single agent.
Data comes in many forms including numbers, words, pixels, imagery, sound and other multi-media, and potentially other types, any of which might be collected into a dataset.
</li>
<li>
<code><a href="#Class:Distribution">dcat:Distribution</a></code> represents an accessible form of a dataset such as a downloadable file.
</li>
<li>
<a href="#Class:Data_Service"><code>dcat:DataService</code></a> represents a data service in a catalog.
A data service is a collection of operations accessible through an interface (API) that provide access to one or more datasets or data processing functions.
</li>
<!--
<li>
<a href="#Class:DataTransformationService"><code>dcat:DataTransformationService</code></a> represents a service that can transform a dataset, e.g. spatial coordinate transformation; interpolation or resampling of a dataset.
</li>
<li>
<a href="#Class:Discovery_Service"><code>dcat:DiscoveryService</code></a> represents a description of a kind of data distribution service that provides access to one or more catalogs to support discovery functions.
</li>
-->
<li>
<a href="#Class:Catalog_Record"><code>dcat:CatalogRecord</code></a> represents a metadata item in the catalog, primarily concerning the registration information, such as who added the item and when.
</li>
</ul>
<figure id="UML_DCAT_All_Attr"><img alt="UML model of DCAT classes and properties" src="UML/DCAT-summary-all-attributes.png">
<figcaption>
Overview of DCAT model, showing the classes of resources that can be members of a Catalog, and the relationships between them.
</figcaption>
</figure>
<p class="note">
Along with the rest of the <a href="#vocabulary-overview">Vocabulary overview</a>, this diagram is <b>non-normative</b>.
Furthermore, while the diagram uses UML-style class notation it should be interpreted following the usual RDF open-world assumptions around the presence/absence of properties, relationships, and their cardinality.
The properties shown in each class reflect those recommended in the descriptions of classes in the <a href="#vocabulary-specification">Vocabulary specification</a>.
To assist in understanding the full scope of each class, properties are copied down from each '::super-class'.
Cardinalities are shown in a few places to reinforce expectations, but these are not axiomatized or enforced in any way by this recommendation.
</p>
<p>
A <b>dataset</b> in DCAT is defined as a "collection of data, published or curated by a single agent, and available for access or download in one or more serializations or formats".
A dataset is a conceptual entity, and can be represented by one or more <b>distributions</b> that serialize the dataset for transfer.
Distributions of a dataset can be provided via <b>data services</b>.
Detailed properties for a data service API are out of the scope of this version of DCAT.
</p>
<p>
A <b>data service</b> in DCAT is a collection of operations or API which provides access to data.
An interactive interface may provide access to the API operations.
A data service typically provides selection, extraction, combination, processing or transformation operations over datasets that might be hosted locally or remote to the service.
A data service might be tied to specific datasets, or its source data might be configured at request- or run-time.
The result of a request to a data service is a representation of a part or all of a dataset or catalog.
A data service might represent a data distribution service to select and download a distribution of a dataset or subset, or a data discovery service to find the description of a suitable dataset.
Other kinds of data service might include data transformation services such as coordinate transformation services, re-sampling and interpolation services, and various data processing services, but these are outside the scope of the current DCAT vocabulary.
</p>
<p>
Descriptions of datasets and data services can be included in a <b>catalog</b>.
A catalog is a kind of dataset whose member items are descriptions of datasets and data services.
Other types of thing might also be catalogued, but the scope of DCAT is currently limited to datasets and data services.
To extend the scope of a catalog beyond datasets and data services it is recommended to define additional sub-classes of <a href="#Class:Resource"><code>dcat:Resource</code></a> in a DCAT application profile or other DCAT application.
To extend the scope of service descriptions beyond data distribution services it is recommended to define additional sub-classes of <a href="#Class:Data_Service"><code>dcat:DataService</code></a> in a DCAT application profile or other DCAT application.
</p>
<div class="note">
<p>
The scope of DCAT 2014 [[?VOCAB-DCAT-20140116]] was limited to catalogs of datasets.
A number of use cases for the revision involve <b>data services</b> as members of a catalog - see <a href="https://www.w3.org/TR/dcat-ucr/#ID6">DCAT Distribution to describe web services - ID6</a> and
<a href="https://www.w3.org/TR/dcat-ucr/#ID18">Modeling service-based data access - ID18</a>.
Hence, the scope of this revision of DCAT includes both datasets and data services to enable these to be part of a DCAT conformant catalog.
Provision for Catalogs to be composed of other Catalogs is also made.
See <a href="https://github.com/w3c/dxwg/issues/172">Issue #172</a>.
</p>
<p>
Catalogs of other kinds of things might be designed following the DCAT pattern, e.g. dealing with facilities, instruments, samples and specimens, other physical artefacts, events or activities.
These are currently out of scope for DCAT, but might be defined through further sub-classes of <a href="#Class:Resource"><code>dcat:Resource</code></a>, which could be specified in a DCAT application profile or other DCAT application.
</p>
</div>
<p>A <b>CatalogRecord</b> describes an entry in the catalog. Notice that while <a href="#Class:Resource"><code>dcat:Resource</code></a> represents the dataset or service itself, <a href="#Class:Catalog_Record"><code>dcat:CatalogRecord</code></a> is the record that describes the registration of an item in the catalog. The use of explicit <a href="#Class:Catalog_Record"><code>dcat:CatalogRecord</code></a> is considered optional. It is used to capture provenance information about entries in a catalog explicitly. If this is not necessary then <a href="#Class:Catalog_Record"><code>dcat:CatalogRecord</code></a> can be safely ignored.</p>
</section>
<section id="dcat-rdf">
<h3>RDF considerations</h3>
<p id="owl2">
The DCAT vocabulary is an OWL2 ontology [[?OWL2-OVERVIEW]] formalized using [[?RDF-SCHEMA]].
Each class and property in DCAT is denoted by an [[?IRI]].
Locally defined elements are in the namespace <a href="http://www.w3.org/ns/dcat#">http://www.w3.org/ns/dcat#</a>.
Elements are also adopted from several external vocabularies, in particular [[?FOAF]], [[?DCTERMS]] and [[?PROV-O]]
</p>
<p id="blankNodes">
RDF allows resources to have global identifiers (IRIs) or to be blank nodes.
Blank nodes can be used to denote resources without explicitly naming them with an IRI.
They can appear in the subject and object position of a triple [[?RDF11-PRIMER]].
For example, in many actual DCAT catalogs, distributions are represented as blank nodes nested inside the related dataset description.
While blank nodes can offer flexibility for some use cases, in a Linked Data context, blank nodes limit our ability to collaboratively annotate data.
A blank node resource cannot be the target of a link and it can't be annotated with new information from new sources.
As one of the biggest benefits of the Linked Data approach is that "anyone can say anything anywhere", use of blank nodes undermines some of the advantages we can gain from wide adoption of the RDF model.
Even within the closed world of a single application dataset, use of blank nodes can quickly become limiting when integrating new data [[?LinkedDataPatterns]].
For these reasons, it is recommended that instances of the DCAT main classes have a global identifier, and use of blank nodes is generally discouraged when encoding DCAT in RDF.
</p>
<p id="rdf-syntax">
All RDF examples in this document are written in Turtle syntax [[?Turtle]] and many are available from the <a href="https://github.com/w3c/dxwg/tree/gh-pages/dcat/examples">DXWG code repository</a>.
</p>
<p class="note">
Each RDF example in this document is intended to demonstrate specific capabilities of DCAT, and therefore only shows a subset of all the potential properties and links which might appear in a complete DCAT resource.
</p>
</section>
<section id="basic-example">
<h3>Basic Example</h3>
<p>This example provides a quick overview of how DCAT might be used to represent a government catalog and its datasets. </p>
<p>First, the catalog description:
</p>
<pre id="ex-catalog" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:catalog
a dcat:Catalog ;
dct:title "Imaginary Catalog" ;
rdfs:label "Imaginary Catalog" ;
foaf:homepage <http://example.org/catalog> ;
dct:publisher :transparency-office ;
dct:language <http://id.loc.gov/vocabulary/iso639-1/en> ;
dcat:dataset :dataset-001 , :dataset-002 , :dataset-003 ;
.
</pre>
<p>The publisher of the catalog has the relative URI <code>:transparency-office</code>. Further description of the publisher can be provided as in the following example:
</p>
<pre id="ex-publisher" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:transparency-office
a foaf:Organization ;
rdfs:label "Transparency Office" ;
.
</pre>
<p>The catalog lists each of its datasets via the <code>dcat:dataset</code> property. In the example above, an example dataset was mentioned with the relative URI <code>:dataset-001</code>. A possible description of it using DCAT is shown below:
</p>
<pre id="ex-dataset" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:dataset-001
a dcat:Dataset ;
dct:title "Imaginary dataset" ;
dcat:keyword "accountability","transparency" ,"payments" ;
dct:creator :finance-employee-001 ;
dct:issued "2011-12-05"^^xsd:date ;
dct:modified "2011-12-15"^^xsd:date ;
dcat:contactPoint <http://example.org/transparency-office/contact> ;
dct:temporal <http://reference.data.gov.uk/id/quarter/2006-Q1> ;
dcat:temporalResolution "P1D"^^xsd:duration ;
dct:spatial <http://www.geonames.org/6695072> ;
dcat:spatialResolutionInMeters "30.0"^^xsd:decimal ;
dct:publisher :finance-ministry ;
dct:language <http://id.loc.gov/vocabulary/iso639-1/en> ;
dct:accrualPeriodicity <http://purl.org/linked-data/sdmx/2009/code#freq-W> ;
dcat:distribution :dataset-001-csv ;
.
</pre>
<p>
Five distinct temporal descriptors are shown for this dataset.
The dataset publication and revision dates are shown in <a href="#Property:resource_release_date"><code>dct:issued</code></a> and <a href="#Property:resource_update_date"><code>dct:modified</code></a>.
For the frequency of update of the dataset in <a href="#Property:dataset_frequency"><code>dct:accrualPeriodicity</code></a>, we use an instance from the <a href="http://www.w3.org/TR/vocab-data-cube/#dsd-cog">Content-Oriented Guidelines</a> developed as part of the <abbr title="World Wide Web Consortium">W3C</abbr> Data Cube Vocabulary [[?VOCAB-DATA-CUBE]] efforts.
The temporal coverage or extent is given in <a href="#Property:dataset_temporal"><code>dct:temporal</code></a> using an item from the Interval dataset (originally available from http://reference.data.gov.uk/id/interval) from data.gov.uk.
The temporal resolution, which describes the minimum spacing of items within the dataset, is given in <a href="#Property:dataset_temporalresolution"><code>dcat:temporalResolution</code></a> using the standard datatype <code>xsd:duration</code>.
</p>
<p>
Additionally, the spatial coverage or extent is given <a href="#Property:dataset_spatial"><code>dct:spatial</code></a> using a URI from <a href="http://www.geonames.org/">Geonames</a>.
The spatial resolution, which describes the minimum spatial separation of items within the dataset, is given in <a href="#Property:dataset_spatialresolution"><code>dcat:spatialResolutionInMeters</code></a> using the standard datatype <code>xsd:decimal</code>.
</p>
<p>
A contact point is provided where comments and feedback about the dataset can be sent.
Further details about the contact point, such as email address or telephone number, can be provided using vCard [[?VCARD-RDF]].
</p>
<p>One representation of the dataset <code>:dataset-001-csv</code> can be downloaded as a 5Kb CSV file. This is
represented as an RDF resource of type <code>dcat:Distribution</code>.
</p>
<pre id="ex-distribution" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:dataset-001-csv
a dcat:Distribution ;
dcat:downloadURL <http://www.example.org/files/001.csv> ;
dct:title "CSV distribution of imaginary dataset 001" ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/csv> ;
dcat:byteSize "5120"^^xsd:decimal ;
.
</pre>
</section>
<section id="classifying-datasets">
<h3>Classifying datasets thematically</h3>
<p>The catalog classifies its datasets according to a set of domains represented by the relative URI <code>:themes</code>. SKOS can be used to describe the domains used:
</p>
<pre id="ex-thematic-classification" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:catalog dcat:themeTaxonomy :themes .
:themes
a skos:ConceptScheme ;
skos:prefLabel "A set of domains to classify documents" ;
.
:dataset-001 dcat:theme :accountability .
</pre>
<p>Notice that this dataset is classified under the domain represented by the relative URI <code>:accountability</code>.
It is recommended to define the concept as part of the concepts scheme identified by the URI <code>:themes</code> that was used to describe the catalog domains. An example SKOS description:
</p>
<pre id="ex-theme-accountability" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:accountability
a skos:Concept ;
skos:inScheme :themes ;
skos:prefLabel "Accountability" ;
.
</pre>
</section>
<section id="classifying-dataset-types">
<h3>Classifying dataset types</h3>
<p>
The type or genre of a dataset can be indicated using the <a href="http://purl.org/dc/terms/type"><code>dct:type</code></a> property.
It is recommended that the value of the property is be taken from a well governed and broadly recognised set of resource types,
such as the <a href="http://dublincore.org/documents/dcmi-terms/#section-7">DCMI Type Vocabulary</a>,
the <a href="https://id.loc.gov/vocabulary/marcgt.html">MARC Genre/Terms Scheme</a>,
the <a href="https://geo-ide.noaa.gov/wiki/index.php?title=ISO_19115_and_19115-2_CodeList_Dictionaries#MD_ScopeCode">ISO 19115 MD_Scope codes</a>,
the <a href="https://schema.datacite.org/meta/kernel-4.1/include/datacite-resourceType-v4.1.xsd">DataCite resource types</a>,
or the PARSE.Insight content-types from Re3data [[?RE3DATA-SCHEMA]].
</p>
<p>
In the following examples, a (notional) dataset is classified separately using values from different vocabularies.
</p>
<pre id="ex-dataset-type" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:dataset-001
rdf:type dcat:Dataset ;
dct:type <http://purl.org/dc/dcmitype/Text> ;
.
:dataset-001
rdf:type dcat:Dataset ;
dct:type <http://id.loc.gov/vocabulary/marcgt/man> ;
.
</pre>
<p>
It is also possible for multiple classifications to be present in a single description.
</p>
<pre id="ex-dataset-multiple-types" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:dataset-001
rdf:type dcat:Dataset ;
dct:type <http://purl.org/dc/dcmitype/Text> ;
dct:type <http://id.loc.gov/vocabulary/marcgt/man> ;
dct:type <http://registry.it.csiro.au/def/datacite/resourceType/Text> ;
dct:type <http://registry.it.csiro.au/def/re3data/contentType/doc> ;
.
<http://registry.it.csiro.au/def/datacite/resourceType/Text>
rdfs:label "Text" ;
dct:source "DataCite resource types" ;
.
<http://registry.it.csiro.au/def/re3data/contentType/doc>
rdfs:label "Standard office documents" ;
dct:source "Re3data content types" ;
.
</pre>
</section>
<section id="describing-catalog-records-metadata">
<h3>Describing catalog records metadata</h3>
<p>If the catalog publisher decides to keep metadata
describing its records (i.e. the records containing metadata
describing the datasets), <code>dcat:CatalogRecord</code> can be used. For example,
while <code>:dataset-001</code> was issued on 2011-12-05, its description on Imaginary Catalog was added on 2011-12-11. This can be represented by DCAT as in the following:
</p>
<pre id="ex-catalog-record" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:catalog dcat:record :record-001 .
:record-001
a dcat:CatalogRecord ;
foaf:primaryTopic :dataset-001 ;
dct:issued "2011-12-11"^^xsd:date ;
.
</pre>
</section>
<section id="example-landing-page">
<h3>Dataset available only behind some Web page</h3>
<p><code>:dataset-002</code> is available as a CSV file. However <code>:dataset-002</code> can only be obtained through some Web page
where the user needs to follow some links, provide some information and check some boxes
before accessing the data.</p>
<pre id="ex-landing-page" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:dataset-002
a dcat:Dataset ;
dcat:landingPage <http://example.org/dataset-002.html> ;
dcat:distribution :dataset-002-csv ;
.
:dataset-002-csv
a dcat:Distribution ;
dcat:accessURL <http://example.org/dataset-002.html> ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/csv> ;
.
</pre>
Notice the use of a <code>dcat:landingPage</code> and the definition of the <code>dcat:Distribution</code> instance.
</section>
<section id="a-dataset-available-as-download-and-behind-some-web-page">
<h3>A dataset available as a download and behind some Web page</h3>
<p>On the other hand, <code>:dataset-003</code> can be obtained through some landing page but also can be downloaded from a known URL.
</p>
<pre id="ex-access-and-download-url" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:dataset-003
a dcat:Dataset ;
dcat:landingPage <http://example.org/dataset-003.html> ;
dcat:distribution :dataset-003-csv ;
.
:dataset-003-csv
a dcat:Distribution ;
dcat:downloadURL <http://example.org/dataset-003.csv> ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/csv> ;
.
</pre>
<p>Notice that we used <code>dcat:downloadURL</code> with the downloadable distribution and that the other distribution accessible through the landing page
does not have to be defined as a separate <code>dcat:Distribution</code> instance.</p>
</section>
<section id="a-dataset-available-from-a-service">
<h3>A dataset available through a service</h3>
<p><code>:dataset-004</code> is distributed in different representations from different services.
The <code>dcat:accessURL</code> for each <code>dcat:Distribution</code> corresponds with the <code>dcat:endpointURL</code> of the service.
Each service is characterized by its general type using <code>dct:type</code> (here using values from the INSPIRE spatial data service type vocabulary),
its specific API definition using <code>dct:conformsTo</code>,
with the detailed description of the individual endpoint parameters and options linked using <code>dcat:endpointDescription</code>.
</p>
<pre id="ex-access-service" class="example nohighlight turtle" aria-busy="false" aria-live="polite">
:dataset-004
rdf:type dcat:Dataset ;
dcat:distribution :dataset-004-csv ;
dcat:distribution :dataset-004-png ;
.
:dataset-004-csv
rdf:type dcat:Distribution ;
dcat:accessService :table-service-005 ;
dcat:accessURL <http://example.org/api/table-005> ;
dcat:mediaType <https://www.iana.org/assignments/media-types/text/csv> ;
.
:dataset-004-png
rdf:type dcat:Distribution ;
dcat:accessService :figure-service-006 ;
dcat:accessURL <http://example.org/api/figure-006> ;
dcat:mediaType <https://www.iana.org/assignments/media-types/image/png> ;
.
:figure-service-006
rdf:type dcat:DataService ;
dct:conformsTo <http://example.org/apidef/figure/v1.0> ;
dct:type <https://inspire.ec.europa.eu/metadata-codelist/SpatialDataServiceType/view> ;
dcat:endpointDescription <http://example.org/api/figure-006/params> ;
dcat:endpointURL <http://example.org/api/figure-006> ;
dcat:servesDataset :dataset-004 ;
.
:table-service-005
rdf:type dcat:DataService ;
dct:conformsTo <http://example.org/apidef/table/v2.2> ;
dct:type <https://inspire.ec.europa.eu/metadata-codelist/SpatialDataServiceType/download> ;
dcat:endpointDescription <http://example.org/api/table-005/capability> ;
dcat:endpointURL <http://example.org/api/table-005> ;
dcat:servesDataset :dataset-003, :dataset-004 ;
. </pre>
</section>
</section>
<section id="vocabulary-specification">
<h2>Vocabulary specification</h2>
<section id="RDF-representation">
<h3>RDF representation</h3>
<p class="ednote">
The DCAT RDF representation is modularized into several files or graphs to help users access a version of DCAT with only the alignments that they need.
This mechanism can also be used to capture different levels of axiomatization, though the status of such proposals has not been finalized.
See <a href="https://github.com/w3c/dxwg/issues/134">Issue #134</a> and the issues enumerated below.
</p>
<!--NoBacklogNorCR div class="issue" data-number="65">
<p>
Guidance on the use DCAT in a weakly-axiomatized environment, such as schema.org, has been identified as a requirement to be satisfied in this revision of DCAT.
</p>
<p>
An <a href="https://raw.githubusercontent.com/w3c/dxwg/gh-pages/dcat/rdf/dcat-schema.ttl">RDF graph containing a proposed alignment of DCAT with schema.org</a> is available. Comments on this alignment are invited.
</p>
</div-->
<p class="issue" data-number="105">
The use of guarded constraints (existence, cardinality, range-type) to control the use of the recommended properties in the context of a class is being considered as part of the revision of DCAT.
</p>
<!--NoBacklogNorCR p class="issue" data-number="110">
The axiomatization of DCAT 2014 used global domain and range constraints for many of the properties defined in the DCAT namespace [[?VOCAB-DCAT-20140116]]. This makes quite strong ontological commitments, some of which are now being reconsidered - see individual issues noted inline below.
</p-->
<p>The (revised) DCAT vocabulary is <a href="https://github.com/w3c/dxwg/tree/gh-pages/dcat/rdf/">available in RDF</a>.
The primary artefact <a href="https://raw.githubusercontent.com/w3c/dxwg/gh-pages/dcat/rdf/dcat.ttl">dcat.ttl</a> is a serialization of the core DCAT vocabulary.
Alongside it are a set of other RDF files that provide additional information, including:</p>
<ol>
<li>
non-normative alignments to other vocabularies, provided for guidance
</li>
<li>
additional axioms, which can be useful in some contexts
</li>
<li>
some profiles of DCAT, including a profile that corresponds to the 2014 version of DCAT [[?VOCAB-DCAT-20140116]]
</li>
</ol>
<!--NoBacklogNorCR p class="issue" data-number="144">
The implementation of a DCAT 2014 profile of the revised DCAT is being considered.
</p -->
</section>
<section id="external-vocab">
<h3>Elements from other vocabularies</h3>
<p>
DCAT requires use of elements from a number of other vocabularies.
Furthermore, DCAT may be augmented by additional elements from external vocabularies, following the usual RDFS [[!RDF-SCHEMA]] and OWL2 [[!OWL2-OVERVIEW]] rules and patterns.
</p>
<section id="complements">
<h4>Complementary vocabularies</h4>
<p>
Elements from a number of complementary vocabularies <em title="MAY" class="rfc2119">MAY</em> be used together with DCAT to provide more detailed information.
For example: properties from the VoID vocabulary [[?VOID]] allow the description of various statistics about a DCAT-described dataset if that dataset is in RDF format; properties from the Provenance ontology [[!PROV-O]] can be used to provide more information about the workflow that generated a dataset or service and related activities and agents; classes and properties from the Organization Ontology [[!VOCAB-ORG]] can be used to explain additional details of responsible agents.
</p>
</section>
<section id="dependencies">
<h4>Element definitions</h4>
<p>
The definitions (including domain and range) of terms outside the DCAT namespace are provided here only for convenience and <em title="MUST NOT" class="rfc2119">MUST NOT</em> be considered normative. The authoritative definitions of these terms are in the corresponding specifications, i.e. [[!DC11]], [[!DCTERMS]], [[!FOAF]], [[!PROV-O]], [[!RDF-SCHEMA]], [[!SKOS-REFERENCE]], [[!XMLSCHEMA11-2]] and [[?VCARD-RDF]].
</p>
</section>
</section>
<section id="Class:Catalog">
<h3>Class: Catalog</h3>
<p>The following properties are recommended for use on this class:
<a href="#Property:catalog_catalog_record">catalog record</a>,
<a href="#Property:catalog_hasPart">hasPart</a>,
<a href="#Property:catalog_dataset">dataset</a>,
<a href="#Property:catalog_service">service</a>,
<a href="#Property:catalog_catalog">catalog</a>,
<a href="#Property:catalog_homepage">homepage</a>,
<a href="#Property:catalog_themes">themes</a>
</p>
<p>The following properties are inherited from the super-class <a href="#Class:Dataset"><code>dcat:Dataset</code></a>:
<a href="#Property:dataset_distribution">distribution</a>,
<a href="#Property:dataset_frequency">frequency</a>,
<a href="#Property:dataset_spatial">spatial/geographic coverage</a>,
<a href="#Property:dataset_spatialresolution">spatial resolution</a>,
<a href="#Property:dataset_temporal">temporal coverage</a>,
<a href="#Property:dataset_temporalresolution">temporal resolution</a>,
<a href="#Property:dataset_wasgeneratedby">was generated by</a>
</p>
<p>The following properties are inherited from the super-class <a href="#Class:Resource"><code>dcat:Resource</code></a>:
<a href="#Property:resource_conformsto">conformsTo</a>,
<a href="#Property:resource_contact_point">contact point</a>,
<a href="#Property:resource_creator">creator</a>,
<a href="#Property:resource_description">description</a>,
<a href="#Property:resource_identifier">identifier</a>,
<a href="#Property:resource_keyword">keyword/tag</a>,
<a href="#Property:resource_landing_page">landing page</a>,
<a href="#Property:resource_language">catalog language</a>,
<a href="#Property:resource_relation">relation</a>,
<a href="#Property:resource_publisher">publisher</a>,
<a href="#Property:resource_release_date">release date</a>,
<a href="#Property:resource_theme">theme/category</a>,
<a href="#Property:resource_title">title</a>,
<a href="#Property:resource_type">type/genre</a>,
<a href="#Property:resource_license">license</a>,
<a href="#Property:resource_rights">rights</a>,
<a href="#Property:resource_update_date">update/modification date</a>,
</p>
<div class="note">
<p>
The scope of DCAT 2014 was catalogs of datasets [[?VOCAB-DCAT-20140116]].
A number of use cases for the revision involve also having <b>data services</b> as members of a catalog - see <a href="https://www.w3.org/TR/dcat-ucr/#ID6">DCAT Distribution to describe web services - ID6</a> and
<a href="https://www.w3.org/TR/dcat-ucr/#ID18">Modeling service-based data access - ID18</a>.
It has been decided to add an explicit class for Data Services in this revision of DCAT, and to enable these to be part of a Catalog.
Provision for Catalogs to be composed of other Catalogs is also enabled.
See <a href="https://github.com/w3c/dxwg/issues/172">Issue #172</a> and <a href="https://github.com/w3c/dxwg/issues/116">Issue #116</a>. </p>
</div>
<table class="definition">
<thead><tr><th>RDF Class:</th><th><a href="http://www.w3.org/ns/dcat#Catalog">dcat:Catalog</a></th></tr></thead>
<tbody>
<tr><td class="prop">Sub-class of:</td><td><a href="#Class:Dataset">Dataset</a></td></tr>
<tr><td class="prop">Definition:</td><td>A curated collection of metadata about datasets and data services</td></tr>
<tr><td class="prop">Usage note:</td><td>A web-based data catalog is typically represented as a single instance of this class.</td></tr>
<tr><td class="prop">See also:</td><td> <a href="#Class:Catalog_Record">Catalog record</a>, <a href="#Class:Dataset">Dataset</a></td></tr>
</tbody>
</table>
<section id="Property:catalog_homepage">
<h4>Property: homepage</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://xmlns.com/foaf/0.1/homepage">foaf:homepage</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A homepage of the catalog (a public web document usually available in HTML).</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://xmlns.com/foaf/0.1/Document">foaf:Document</a></td></tr>
<tr><td class="prop">Usage note:</td><td><a href="http://xmlns.com/foaf/0.1/homepage"><code>foaf:homepage</code></a> is an inverse functional property (IFP) which means that it <em title="MUST" class="rfc2119">MUST</em> be unique and precisely identify the web-page for the resource. This property indicates the canonical web-page, which might be helpful in cases where there is more than one web-page about the resource.</td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_themes">
<h4>Property: themes</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#themeTaxonomy">dcat:themeTaxonomy</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A knowledge organization system (KOS) used to classify catalog's datasets and services.</td></tr>
<tr><td class="prop">Domain:</td><td><a href="#Class:Catalog"><code>dcat:Catalog</code></a></td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2004/02/skos/core#ConceptScheme"><code>skos:ConceptScheme</code></a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_hasPart">
<h4>Property: hasPart</h4>
<p class="note">
Explicit use of this property added in this revision of DCAT.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/hasPart">dct:hasPart</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>An item that is listed in the catalog.</td></tr>
<tr><td class="prop">Domain:</td><td><a href="#Class:Catalog"><code>dcat:Catalog</code></a></td></tr>
<tr><td class="prop">Range:</td><td><a href="#Class:Resource"><code>dcat:Resource</code></a></td></tr>
<tr><td class="prop">Usage note:</td><td>This is the most general predicate for membership of a catalog. Use of a more specific sub-property is recommended when available. </td></tr>
<tr><td class="prop">See also:</td><td>Sub-properties of <code>dct:hasPart</code> in particular <a href="#Property:catalog_dataset"><code>dcat:dataset</code></a>, <a href="#Property:catalog_catalog"><code>dcat:catalog</code></a>, <a href="#Property:catalog_service"><code>dcat:service</code></a>. </td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_dataset">
<h4>Property: dataset</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#dataset">dcat:dataset</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A collection of data that is listed in the catalog.</td></tr>
<tr><td class="prop">Sub property of:</td><td><a href="http://purl.org/dc/terms/hasPart"><code>dct:hasPart</code></a></td></tr>
<tr><td class="prop">Domain:</td><td><a href="#Class:Catalog"><code>dcat:Catalog</code></a></td></tr>
<tr><td class="prop">Range:</td><td><a href="#Class:Dataset"><code>dcat:Dataset</code></a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_service">
<h4>Property: service</h4>
<p class="note">
Property added in this revision of DCAT.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#service">dcat:service</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A site or end-point that is listed in the catalog.</td></tr>
<tr><td class="prop">Sub property of:</td><td><a href="http://purl.org/dc/terms/hasPart"><code>dct:hasPart</code></a></td></tr>
<tr><td class="prop">Domain:</td><td><a href="#Class:Catalog"><code>dcat:Catalog</code></a></td></tr>
<tr><td class="prop">Range:</td><td><a href="#Class:Data_Service"><code>dcat:DataService</code></a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_catalog">
<h4>Property: catalog</h4>
<p class="note">
Property added in this revision of DCAT.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#catalog">dcat:catalog</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A catalog whose contents are of interest in the context of this catalog</td></tr>
<tr><td class="prop">Sub property of:</td><td><a href="http://purl.org/dc/terms/hasPart"><code>dct:hasPart</code></a></td></tr>
<tr><td class="prop">Domain:</td><td><a href="#Class:Catalog"><code>dcat:Catalog</code></a></td></tr>
<tr><td class="prop">Range:</td><td><a href="#Class:Catalog"><code>dcat:Catalog</code></a></td></tr>
</tbody>
</table>
</section>
<section id="Property:catalog_catalog_record">
<h4>Property: catalog record</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#record">dcat:record</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A record describing the registration of a single dataset or dataservice that is part of the catalog.</td></tr>
<tr><td class="prop">Domain:</td><td><a href="#Class:Catalog"><code>dcat:Catalog</code></a></td></tr>
<tr><td class="prop">Range:</td><td><a href="#Class:Catalog_Record"><code>dcat:CatalogRecord</code></a></td></tr>
</tbody>
</table>
</section>
</section> <!-- end Class:Catalog -->
<section id="Class:Resource">
<h3>Class: Catalogued Resource</h3>
<p>The following properties are recommended for use on this class:
<a href="#Property:resource_accessRights">accessRights</a>,
<a href="#Property:resource_conformsto">conformsTo</a>,
<a href="#Property:resource_contact_point">contact point</a>,
<a href="#Property:resource_creator">creator</a>,
<a href="#Property:resource_description">description</a>,
<a href="#Property:resource_hasPolicy">hasPolicy</a>,
<a href="#Property:resource_identifier">identifier</a>,
<a href="#Property:resource_keyword">keyword/tag</a>,
<a href="#Property:resource_landing_page">landing page</a>,
<a href="#Property:resource_license">license</a>,
<a href="#Property:resource_language">resource language</a>,
<a href="#Property:resource_relation">relation</a>,
<a href="#Property:resource_rights">rights</a>,
<a href="#Property:resource_qualifiedRelation">qualified relation</a>,
<a href="#Property:resource_publisher">publisher</a>,
<a href="#Property:resource_release_date">release date</a>,
<a href="#Property:resource_theme">theme/category</a>,
<a href="#Property:resource_title">title</a>,
<a href="#Property:resource_type">type/genre</a>,
<a href="#Property:resource_update_date">update/modification date</a>,
<a href="#Property:resource_qualifiedAttribution">qualified attribution</a>
</p>
<p class="issue" data-number="62">
The possible association of items with zero or multiple catalogs has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
<p class="issue" data-number="71">
The need to be able to describe the business or project context related to production of a catalogued resource has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
<!--
-- this issue already closed - prov:wasGeneratedBy added to dcat:Dataset (but not to dcat:Resource) --
<p class="issue" data-number="77">
The need to be able to link a catalogued resource with the business or project context of its production has been identified as a requirement to be satisfied in the revision of DCAT.
</p>
-->
<table class="definition">
<thead><tr><th>RDF Class:</th><th><a href="http://www.w3.org/ns/dcat#Resource">dcat:Resource</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Resource published or curated by a single agent.</td></tr>
<tr><td class="prop">Usage note:</td><td>The class of all catalogued resources, the superclass of
<a href="#Class:Dataset"><code>dcat:Dataset</code></a>, <a href="#Class:Data_Service"><code>dcat:DataService</code></a>, <a href="#Class:Catalog"><code>dcat:Catalog</code></a> and any other member of a <a href="#Class:Catalog"><code>dcat:Catalog</code></a>.
This class carries properties common to all catalogued resources, including datasets and data services.
It is strongly recommended to use a more specific sub-class when available.</td></tr>
<tr><td class="prop">Usage note:</td><td><a href="#Class:Resource"><code>dcat:Resource</code></a> is an extension point that enables the definition of any kind of catalog. Additional subclasses may be defined in a DCAT application profile or other DCAT application for catalogs of other kinds of resources</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Class:Catalog_Record" title="">Catalog record</a></td></tr>
</tbody>
</table>
<p class="note">
The class <a href="#Class:Resource"><code>dcat:Resource</code></a> has been added to the DCAT vocabulary in this revision.
</p>
<section id="Property:resource_accessRights">
<h4>Property: accessRights</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/accessRights">dct:accessRights</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>A rights statement that concerns how the resource is accessed.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://purl.org/dc/terms/RightsStatement"><code>dct:RightsStatement</code></a></td></tr>
<tr><td class="prop">Usage note:</td><td>Information about licenses and rights <em title="MAY" class="rfc2119">MAY</em> be provided for the Resource. See also guidance at <a href="#license-rights">License and rights statements</a>.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Property:resource_rights" title="">resource rights</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_conformsto">
<h4>Property: conforms to</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/conformsTo">dct:conformsTo</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>An established standard to which the described catalogued resource conforms.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://purl.org/dc/terms/Standard"><code>dct:Standard</code></a> (A basis for comparison; a reference point against which other things can be evaluated.)</td></tr>
<tr><td class="prop">Usage note:</td><td>This property <em title="SHOULD" class="rfc2119">SHOULD</em> be used to indicate the model, schema, ontology, view or profile that the catalogued resource content conforms to. </td></tr>
</tbody>
</table>
</section>
<p class="note">
<a href="http://purl.org/dc/terms/Standard"><code>dct:Standard</code></a> is defined as "A basis for comparison; a reference point against which other things can be evaluated." The target resource is not restricted to formal standards issued by bodies like <abbr title="International Organization for Standardization">ISO</abbr> and W3C. In this context, it is any resource that specifies one or more aspects of the catalogued resource content, for example schema, semantics, syntax, usage guidelines, file format, or specific serialization. The meaning of conformance is determined by provisions in the target standard.
</p>
<section id="Property:resource_contact_point">
<h4>Property: contact point</h4>
<p class="note">
In DCAT 2014 [[VOCAB-DCAT-20140116]] the domain of <code>dcat:contactPoint</code> was <code>dcat:Dataset</code>, which limited use of this property in other contexts. The domain has been relaxed in this revision - see <a href="https://github.com/w3c/dxwg/issues/95">Issue #95</a>.
</p>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://www.w3.org/ns/dcat#contactPoint">dcat:contactPoint</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>Relevant contact information for the catalogued resource. Use of vCard is recommended [[?VCARD-RDF]]. </td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2006/vcard/ns#Kind"><code>vcard:Kind</code></a></td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_creator">
<h4>Property: resource creator</h4>
<div class="note">
<p>
New property added in this revision of DCAT, specifically added when considering the data citation requirement and
added to the <a href="#Class:Resource"><code>dcat:Resource</code></a> class, as the Dataset superclass. For more details, see
the <a href="#data-citation">data citation</a> section.
</p>
<p>
The use of the [[?PROV-O]] qualified-attribution pattern is <a href="#qualified-attribution">described below</a>.
`dct:creator` corresponds with a general attribution with the role 'creator'.
</p>
</div>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/creator">dct:creator</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>The entity responsible for producing the resource.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://xmlns.com/foaf/0.1/Agent"><code>foaf:Agent</code></a></td></tr>
<tr><td class="prop">Usage note:</td><td>Resources of type <a href="http://xmlns.com/foaf/0.1/Agent"><code>foaf:Agent</code></a>
are recommended as values for this property.</td></tr>
<tr><td class="prop">See also:</td><td><a href="#Class:Organization_Person">Class: Organization/Person</a></td></tr>
</tbody>
</table>
</section>
<section id="Property:resource_description">
<h4>Property: description</h4>
<table class="definition">
<thead><tr><th>RDF Property:</th><th><a href="http://purl.org/dc/terms/description">dct:description</a></th></tr></thead>
<tbody>
<tr><td class="prop">Definition:</td><td>free-text account of the item.</td></tr>
<tr><td class="prop">Range:</td><td><a href="http://www.w3.org/2000/01/rdf-schema#Literal"><code>rdfs:Literal</code></a></td></tr>
</tbody>
</table>