1. Semantic Objects

2. Definitions
A semantic object is a named collection of attributes that sufficiently describes a distinct identity
Semantic objects are grouped into classes each of which has a name
A semantic object has a collection of attributes
Objects represent distinct identities that users recognize as independent and separate and that they want to track and report

3. More definitions Simple attributes have a single element
Group attributes are composites of other attributes
Semantic object attributes are attributes that establish a relationship between one semantic object and another

4. Example to consider What are the simple attributes?
What are the group attributes?
What are the semantic object attributes?

5. Attribute Cardinality
Each attribute has a minimum cardinality
ususally 0 or 1
Each attribute has a maximum cardinality
usually 1 or n
Cardinalities are shown in format n.m where
n is the minimum cardinality and
m is the maximum cardinality
Cardinalities of groups and attributes of groups can be subtle

6. Example What is the minimum cardinality of CampusAddress?
What is the minimum cardinality of Building?
Note: cardinalities operate only between the attribute and the container of the attribute.

7. Object Instance

8. Paired Attributes THERE ARE NO ONE-WAY OBJECT RELATIONSHIPS.
IF AN OBJECT CONTAINS ANOTHER OBJECT, THEN THE SECOND OBJECT WILL CONTAIN THE FIRST.

9. More definitions
An object identifier is one or more object attributes that the users employ to identify object instances.
A group identifier is an identifier that has more than one attribute
The domain of an attribute is a description of the attribute’s possible values
The domain of a simple attribute consists of both a physical and a semantic description
The domain of a group attribute also consists of both a physical and a semantic description

10. Still more definitions
The portion of an object that is visible to a particular application is called the semantic object view or simply the view.

11. Types of Attributes Necessary to describe types of objects
A single-value attribute is an attribute whose maximum cardinality is one
A multivalue attribute is one whose maximum cardinality is greater than one
A nonobject attribute is a simple or group attribute

12. Types of Objects Simple Composite Compound Hybrid Association Objects
Parent Subtype Objects
Archetype/Version Objects

13. Simple Objects
A simple object is a semantic object that contains only single-value, simple or group attributes.

14. Transformation of Simple Object

15. Composite Objects
A composite object is a semantic object that contains one or more multivalue simple or group attributes but no object attributes.

16. Transformation of a Composite Object

17. Transformation of a Composite Object - separate group attributes

18. Transformation of a Composite Object - nested group attributes

19. Compound Objects 1:1
A compound object contains at least one object attribute.

20. Transformation of a Compound Object – 1:1

21. Transformation of a Compound Object – 1:1 – Two ways

22. Compound Objects 1:N or N:1

23. Transforming a Compound Object 1:N or N:1

24. Compound Objects N:M

25. Transformation of Compound Objects N:M