This document discusses mandatory and disjunctive mandatory rules in conceptual data modeling. It defines mandatory roles as those where the population of the role is equal to the population of the entity type. Disjunctive mandatory roles specify that an entity must play at least one of several roles. Examples are provided of making roles mandatory and defining disjunctive mandatory and external uniqueness constraints. The document also discusses reference schemes and compares conceptual modeling to Entity-Relationship and UML modeling.

1. ‫أكاديمية الحكومة اإللكترونية الفلسطينية‬
The Palestinian eGovernment Academy
www.egovacademy.ps
Tutorial 1: Data and Business Process Modeling
Session 3.2
Mandatory Rules
Prof. Mustafa Jarrar
Sina Institute, University of Birzeit
mjarrar@birzeit.edu
www.jarrar.info
Reviewed by
Prof. Marco Ronchetti, Trento University, Italy
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2. About
This tutorial is part of the PalGov project, funded by the TEMPUS IV program of the
Commission of the European Communities, grant agreement 511159-TEMPUS-1-
2010-1-PS-TEMPUS-JPHES. The project website: www.egovacademy.ps
Project Consortium:
Birzeit University, Palestine
University of Trento, Italy
(Coordinator )
Palestine Polytechnic University, Palestine Vrije Universiteit Brussel, Belgium
Palestine Technical University, Palestine
Université de Savoie, France
Ministry of Telecom and IT, Palestine
University of Namur, Belgium
Ministry of Interior, Palestine
TrueTrust, UK
Ministry of Local Government, Palestine
Coordinator:
Dr. Mustafa Jarrar
Birzeit University, P.O.Box 14- Birzeit, Palestine
Telfax:+972 2 2982935 mjarrar@birzeit.eduPalGov © 2011
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3. © Copyright Notes
Everyone is encouraged to use this material, or part of it, but should properly
cite the project (logo and website), and the author of that part.
No part of this tutorial may be reproduced or modified in any form or by any
means, without prior written permission from the project, who have the full
copyrights on the material.
Attribution-NonCommercial-ShareAlike
CC-BY-NC-SA
This license lets others remix, tweak, and build upon your work non-
commercially, as long as they credit you and license their new creations
under the identical terms.
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4. Tutorial Map
Intended Learning Objectives
Topic Time
Module 1 (Conceptual Date Modeling)
Module I: Conceptual Data Modeling
A: Knowledge and Understanding
11a1: Demonstrate knowledge of conceptual modeling notations and concepts Session 0: Outline and Introduction
11a2: Demonstrate knowledge of Object Role Modeling (ORM) methodology. Session 1.1: Information Modeling 1
11a3: Explain and demonstrate the concepts of data integrity & business rules Session 1.2: Conceptual Data Modeling using ORM 1
B: Intellectual Skills Session 1.3: Conceptual Analyses 1
11b1: Analyze application and domain requirements at the conceptual level, Session 2: Lab- Conceptual Analyses 3
and formalize it using ORM. Session 3.1: Uniqueness Rules 1.5
11b2: Analyze entity identity at the application and domain levels. Session 3.2: Mandatory Rules 1.5
11b4: Optimize, transform, and (re)engineer conceptual models. Session 4: Lab- Uniqueness & Mandatory Rules 3
11b5: Detect &resolve contradictions & implications at the conceptual level. Session 5: Subtypes and Other Rules 3
C: Professional and Practical Skills Session 6: Lab- Subtypes and Other Rules 3
11c1: Using ORM modeling tools (Conceptual Modeling Tools). Session 7.1: Schema Equivalence &Optimization 1.5
Module 2 (Business Process Modeling) Session 7.2: Rules Check &Schema Engineering 1.5
A: Knowledge and Understanding Session 8: Lab- National Student Registry 3
12a1: Demonstrate knowledge of business process modeling notations and concepts.
Module II: Business Process Modeling
12a2: Demonstrate knowledge of business process modeling and mapping.
12a3: Demonstrate understand of business process optimization and re-engineering. Session 9: BP Management and BPMN: An Overview 3
B: Intellectual Skills Session 10: Lab - BP Management 3
12b1: Identify business processes. Session 11: BPMN Fundamentals 3
12b2: Model and map business processes. Session 12: Lab - BPMN Fundamentals 3
12b3: Optimize and re-engineer business processes. Session 13: Modeling with BPMN 3
C: Professional and Practical Skills Session 14: Lab- Modeling with BPMN 3
12c1: Using business process modeling tools, such as MS Visio. Session 15: BP Management & Reengineering 3
Session 16: Lab- BP Management & Reengineering 3
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5. Session ILOs
After completing this session students will be able to:
11a3: Explain and demonstrate the concepts of data integrity and
business rules.
11b1: Analyze application and domain requirements at the
conceptual level, and formalize it using ORM.
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6. Conceptual Schema Design Steps
1. From examples to elementary facts
2. Draw fact types and apply population check
3. Combine entity types
4. Add uniqueness constraints
5. Add mandatory constraints
6. Add set, subtype, & frequency constraints
7. Final checks, & schema engineering issues
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7. Mandatory Versus Optional
Any problem with this table?
By default, all roles are optional.
How can we say that a role is mandatory?
each Patient Has at least one PatientName
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8. Mandatory Roles
 Mandatoriness is implied with Value Types
(by default).
For example: it is assumed that “each
PhoneNr is for at least one Patient”, because
PhoneNr is a Value Type.
??
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9. Mandatory Definition
Role r is mandatory (for the population of A)
Each instance of type A that is recorded in the database is
also recorded to play r
pop( r) = pop( A)
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10. Mandatory Roles
How can we decide to make a role mandatory?
Recall our discussion on
(Conceptual data modeling) versus (conceptual modeling)
If a role is mandatory in the real world, it may be optional in the model.
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11. Disjunctive Mandatory
How to say that it is mandatory for each member to (PlaysFor | Coaches)
a team, or both. We cannot have both roles optional, at least one role
should be played.
Disjunctive mandatory constraint:
Each Member coaches or plays (or both).
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12. Disjunctive Mandatory
Alternative notations for disjunctive mandatory role constraint.
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13. Definition of Disjunctive Mandatory
Disjunctive mandatory role constraint
The inclusive disjunction of roles r1...rn is mandatory for A
i.e., each member of pop(A) plays r1 or r2 ...or rn (or all)
i.e., each member of pop(A) plays at least one of r1 … rn
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14. Another Example
Each person must be a parent or a child.
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15. Back to Uniqueness
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16. External Uniqueness
How to say that the combination of (Discipline, YearLevel, SerialNr) is
unique for each subject?
The Subject code might be generated from this combination
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17. Another Example
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18. Reference Schemes
In data modeling, each entity (i.e., Object Type) must have an identity.
The identity is achieved if an entity has a mandatory and unique role
This is not important (i.e. implicit) in ontology modeling.
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19. Discussion
Summarize what you learned? And what you think about it?
Compare what you learned with EER and UML?
Questions & Suggestions?
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20. References
1. Information Modeling and Relational Databases: From
Conceptual Analysis to Logical Design, Terry Halpin (ISBN 1-
55860-672-6) – Chapter 5.
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