BBY 464 Semantic Information Management
(Spring 2016)
Data and Metadata
Management
Yaşar Tonta & Orçun Madran
[yasartonta, orcunmadran]@gmail.com
Hacettepe University
Department of Information Management
Semantic Web
Web 3.0 = Web 2.0 + Semantic Web
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•
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Social semantic Web
Meaning
Locating and fusing information automatically
Performing basic reasoning
Source: Mark Greaves, Peter Mika. Semantic Web and Web 2.0, In J. Web Sem., 6(1):1-3, 2008
Metadata
• Structured description for all types of
information resources
• Tagging (web content)
• Metadata is
– artificial (no metadata in the nature)
– Constructive (can be used to solve problems)
– Actionable (can be used to meet some info needs)
Source: Glushko, 2013
Metadata
• Artificial
• Constructive
• Actionable
DNA Metadata
Source: Coyle, 2010
http://www.techlicious.com/blog/google-photos-gorilla-african-american-blunder/
Comparing fields
Source: http://classes.slis.lsu.edu/wu/7410/sp13/jfrench/HW2.pdf
MARC to DC Crosswalk
Source: http://classes.slis.lsu.edu/wu/7410/sp13/jfrench/HW2.pdf
XML-RDF Converter
A Data Modeling Process
• Steps in the data modeling process
– Plan project
– Determine requirements
– Specify entities
– Specify relationships
– Determine identifiers
– Specify attributes
– Specify domains
– Validate model
Chapter 3/14
Copyright © 2004
Validating Model
• Data model is a model of humans’ models,
not a model of reality
• A data model is wrong if it does not accurately reflect the
ways the users think about their world
• Data models are validated through a series of reviews
– Normally, a team review is followed by user reviews
• E-R model as well as prototypes of forms and reports may be
used to communicate to users features of the data model
Chapter 3/15
Copyright © 2004
E-R Model
• Entity-Relationship model is a set of concepts and graphical
symbols that can be used to create conceptual schemas
• Four versions
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Original E-R model by Peter Chen (1976)
Extended E-R model: the most widely used model
Information Engineering (IE) by James Martin (1990)
IDEF1X national standard by the National Institute of Standards and
Technology
– Unified Modeling Language (UML) supporting
object-oriented methodology
Chapter 2/16
Copyright © 2004
Example: E-R Diagram
Chapter 2/17
Copyright © 2004
Binary Relationships
• 1:1
• 1:N
• N:M
Chapter 2/18
Copyright © 2004
Example: Identifying Connection
Relationships
Chapter 3/19
Copyright © 2004
Example: University System
Chapter 3/20
Copyright © 2004
IDEF1X Standard
• IDEF1X (Integrated Definition 1, Extended) was announced as a national
standard in 1993
• It defines entities, relationships, and attributes in more specific meanings
• It changed some of the E-R graphical symbols
• It includes definition of domains, a component not present in the
extended E-R model
• Four Relationship Types
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Non-Identifying Connection Relationships
Identifying Connection Relationships
Non-Specific Relationships
Categorization Relationships
• Products supporting IDEF1X: ERWin, Visio, Design/2000
Chapter 2/22
Copyright © 2004
Example: IDEF1X
Chapter 2/23
Copyright © 2004
UML-style E-R Diagrams
• The Unified Modeling Language (UML) is a set of structures and
techniques for modeling and designing object-oriented programs (OOP)
and applications
• The concept of UML entities, relationships, and attributes are very similar
to those of the extended E-R model
• Several OOP constructs are added:
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<Persistent> indicates that the entity class exist in the database
UML allows entity class attributes
UML supports visibility of attributes and methods
UML entities specify constraints and methods in the third segment of the
entity classes
• Currently, the object-oriented notation is of limited practical value
Chapter 2/24
Copyright © 2004
Example: UML
Chapter 2/25
Copyright © 2004
Example: UML
Chapter 2/26
Copyright © 2004
Example: UML
Chapter 2/27
Copyright © 2004
Database
Dictionary for a Database
Object Relational Database
ER & OO Schemas
Dictionary for an ER Model
Dictionary for an OO Model
Four parts of dictionary
Supermodel in the metalevel directory
Description of some models in the
dictionary
Model-generic dictionary based on
supermodel