(Journal #7) 7th Day of Class

The 7th day of our class is the continuation of our last topic. The continuation of our discussion is the Data Modeling which we didn’t finish discussing due to the lack of time.We continued with the Conceptual and Logical Data Modeling, Mapping the Conceptual to Logical Data Model and their 9 types of mapping.

  1. Regular Entities
  2. Composite Attributes
  3.  Multi valued Attributes
  4.  Weak Entities
  5. Associative Entities
  6. Binary Relationships
  7. Unary Relationships
  8. Ternary Relationships
  9. Generalization Relationships

This are the guides in mapping from conceptual to logical data modeling. As the discussion goes Prof. Arvin give examples of mapping this are the 3 Mapping Binary Relationships: One-to-Many is the Primary Key on one side becomes a Foreign Key on the many side. Many-to-Many create an Associative Entity with the Primary Key of each table becoming the Composite Key of the Associative Entity. One-to-One is the Primary Key of one side become the foreign key on the other side. The most common relationship is the One-to-Many relationship is reduce redundancy and more systematic and order. Which he explained each kind for us to further how it is being done and why it is important to be done. Lastly he discussed the Normalization wherein it is composed of 5NF (5 Normal Form). This part is the decides which attributes should be grouped together in a relation and it reduces redundancy that waste storage and capacity.

The main concept of this normalization is not just to reduce redundancy it also deals with the data to be in the organize relation with other entity. This will also help the one doing the normalization manipulate the form that is being normalize.

 

 

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