Ch 4 - Semantic Object Model

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					Ch 4 - Semantic Object Model

Object-Oriented Modeling (Semantic Object Model) with Object-Oriented Prog Language
Relationships between entities (ER Diagrams) with Relational Programming Languages

In-Class Quiz - what is the major difference between object and relational modeling?

Object Modeling includes Behavior (Relationships; Calculations; Reactions)
        Objects are stand-alone models complete user view on What a Customer is?

Types of behaviors/attributes -
        Simple attributes - single value
        Group attributes - two or more attributes combined for meaning (Name; Address)
        Semantic Object attributes - attributes which establish relationships

Look at page 76, figure 4-2…identify each type of attribute

All relationships are between objects; if a Semantic Object attribute is included in one object it must be
included in the matching object

***Remember Semantic Object Models stand alone, so cardinality needs to be included.

Look at page 81, figur3e 4-6…draw on board

In-Class Quiz - which ones are mandatory? Which ones are optional? Only one? Many?
        Write the business rules that support your findings.

         A specific College may have a Campus Address but it might not.
         A specific Campus Address belongs to only one College.
         A Campus Address must have one and only one Building and Office Number.
         A specific College has at least one Department but can have many.
         A specific Department belongs to one and only one College.

College and Department can both stand alone.

Look at the domains shown on pages 86 and 87, they are similar to what? Data Dictionary

Data Dictionaries and domains include information necessary for development and understanding of the
implemented database.
        Types - F=Formula; Simple; G=Group; SO=Semantic Object What else?
                  A= Audio Clip; Video Clip; P=Photos (depends on business)

Like ERDs, semantic objects come in different complexities/types of objects…
       Simple - contains only single-valued attributes
       Composite - contains multi-valued attributes (i.e. textbooks requir3ed for a course)
       Compound - contains semantic objects (i.e. relationships to other objects)
       Hybrid - at least one multi-valued attribute and one semantic object attribute (combination of
Composite and Compound)
       Association - relates two or more objects and stores attributes specific to relationship

         Look at page 99, figure4-26; many-to-many relationship with specific attributes
         Parent/SubType - like SuperType/SubTypes or SuperClass/SubClass
         Draw Students (P) with UnderGrad (ST) and Graduate (ST)
         Archetype/Version - dividing attributes that change over time and those that don't
         Draw Textbook and Next Edition information; look at page 104, figure 4-31
In Groups - discuss the Semantic Object Model on page 96, figure 4-24
       What is the model's purpose?
       Which attributes are calculations? Groups? Multi-valued?
       Write the business rules that support the semantic object attributes included.
       Create an ERD to represent the business rules just created.
       Add the applicable attributes to the ERD just created.

Compare ERD to the diagram on page 105, figure 4-34

*** InClass – FiredUp small groups page 116

				
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