An introduction to metadata. Metadata registries for improved data management

Transcription

1 This afternoon An introduction to metadata Metadata registries for improved data management within the Highways Agency An introduction to metadata 1

2 My agenda What is metadata? Metadata standards What is Metadata? "Metadata is data about data" metadata for data management metadata for content management metadata for describing data values 2

3 Data v metadata? Author: Title: GORDON, Keith Principles of Data Management: Facilitating Information Sharing Publisher: British Computer Society Publication date: ISBN: August For a Librarian, this is Metadata Data v metadata? Author: Title: GORDON, Keith Principles of Data Management: Facilitating Information Sharing Publisher: British Computer Society Publication date: ISBN: For a Data Manager, this is Metadata August For a Data Manager, this is Data 3

4 Data v metadata? Or, as data in a table: ISBN Author Title Pub Pub Date Gordon, Keith Principles of BCS For a Librarian, this is Metadata Or, as data in a table: Data v metadata? ISBN Author Title Pub Pub Date For a Data Manager, this is Metadata Gordon, Keith Principles of BCS For a Data Manager, this is Data 4

5 Data v metadata? Describing values? Name Picture Hair Colour Eye Colour Spectacles Birthdate Gordon, Keith Light Brown Hazel Yes Is this metadata? Metadata for data management The database schema User identifiers and user authorization Electronic The currency of the data A lexicon of words and terms used in data names and any associated abbreviation schemes Paper Logical data structures and the associated data integrity rules A glossary of business words, terms and abbreviations that support data use 5

6 Metadata for content management Dublin Core Metadata Element Set Online Computer Library Center Contributor Coverage Creator Date Description Format Identifier Language World Wide Web Consortium (W3C) Publisher Relation Rights Source Subject Title Type Standard for Learning Object Metadata Institute of Electrical and Electronics Engineers (IEEE) Resource Description Framework (RDF) Agricultural Metadata Element Set (AgMES) Food and Agriculture Organization (FAO) of the United Nations. Metadata for describing data values Internal How the data is to be processed and displayed Bitmap Header BMP file identifies the file as a bitmap file Bitmap Information height, width, etc Color Palette the definition of the colours being used Bitmap Data describes the image External To help with querying Hair colour, eye colour, etc 6

7 My agenda What is metadata? Metadata standards ISO/IEC JTC1 SC32 WG2 - Metadata 7

8 (Too?) many standards Metadata registries (ISO/IEC 11179) Framework for metamodel interoperability (ISO/IEC 19763) Metadata registry - interoperability and bindings (ISO/IEC 20944) Procedures for achieving metadata registry content consistency (ISO/IEC 20943) Metadata registry modules (ISO/IEC 19773) Representation of data element values (ISO/IEC 14957) Metadata for technical standards and specification documents (ISO/IEC 24706) Common Logic (ISO/IEC 24707) Metadata registries (MDR) (ISO/IEC 11179) Part 1 Part 2 Part 3 Part 4 Part 5 Part 6 Framework Classification Registry Metamodel and Basic Attributes Formulation of Data Definitions Naming and Identification Principles Registration 8

9 MDR key concepts Data Element Concept specified by specification for Conceptual Domain expressed by represented by expression of representation of Data Element representation of represented by Value Domain MDR key concepts data_element_conceptual_domain_relationship Data_Element_Concept 0.. n Conceptual_Domain having specifying expressed_by represented by data_element_concept_expression conceptual_domain_representation 0.. n expressing representing 0.. n Data_Element 0.. n Value_Domain representing represented_by data_element_representation 9

10 The data element concept The Country Identifiers conceptual domain... has possible data elements... Afghanistan Belgium China Denmark Egypt France Germany etc Afghanistan Belgium China Denmark Egypt France Germany etc AFG BEL CHN DNK EGY FRA DEU etc etc ISO 3166 English Name ISO Alpha Code ISO Numeric Code Administered items Administered Item (m) administration record Data Element Concept Data Element Conceptual Domain Value Domain Representation Class Classification Scheme Object Class Context Derivation Rule Property 10

11 Problems with Concentrates on "data elements" Where are the sets of elements (entities) and the relationships between them? Ah! We need the Extended Metadata Repository (XMDR) project - involves US agencies not ISO/IEC -but Framework for metamodel interoperability (FMI) (ISO/IEC 19763) Part 1 Part 2 Part 3 Part 4 Part 5 Part 6 Reference model Core model Metamodel for ontology registration Metamodel for model mapping Metamodel for model constructs Registration procedures 11

12 Framework for metamodel interoperability (FMI) (ISO/IEC 19763) Part 1: Reference model Part 2: Core model Part 3: Metamodel for ontology registration Part 4: Metamodel for model mapping Part 5: Metamodel for model constructs Part 6: Registration procedures Framework for metamodel interoperability (FMI) (ISO/IEC 19763) Core model Metamodel instance Model Mapping Describing Metamodel Model Mapping Metamodel Describing Metamodel Metamodel Registry Metamodel Registry Buyer Seller Buyer Seller Industry Domain A Industry Domain B 12

13 An aside Information Resource Dictionary System (IRDS) M3 Definition of concepts used to define dictionaries IRD Definition Schema IRD Schema Definition Level 'Dictionary Object' M2 IRD Schema defines types at IRD level IRD Archived definitions IRD under definitions development IRD Definition Data to support added value facilities IRD Definition Level Entity Type Attribute Relationship Domain M1 Application Schema defines types at Application Level IRD Result of analysis, design and other information IRD Level Employee Name Employee Birth Date M0 Meta Object Facility levels Application Database Application Level John Smith 23 June 1956 FMI with the MOF levels MOF model M3 FMI core model FMI model mapping UML metamodel UML <-> IDEF1X model mapping metamodel IDEF1X metamodel M2 UML model construct UML <-> IDEF1X model construct mapping IDEF1X model construct Class Class <-> Entity mapping Entity M1?? <-> Person Person M0 :???? :???? <-> Taro Yamada : Taro Yamada :?????? :?????? <-> John Smith : John Smith 13

14 Any questions? 14