Please see attachment, there are two portions.

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Please see attachment, there are two portions.


Part 1: Entity relationship models are limited in what they can express. It helps to be aware of the limitations up front, since they can affect the choices you make as to how you represent the enterprise you are modeling. Describe some of the ER design limitations, and discuss how understanding these limitations will influence how you choose to model a particular situation, so that you are able to represent the things that are most important. Part 2: Prior to beginning this assignment, review Chapter 3: The Relational Database Model and Chapter 4: Entity Relationship (ER) Modeling from the course text and read Enhanced Entity-Relationship Model (Links to an external site.). A superclass is an entity type that has one or more distinct subgroups with unique attributes. The subgroups with unique attributes are defined as subclasses. There are several reasons for introducing superclass and subclasses into an ER model. First, incorporating a superclass and subclasses maintains the cleanliness of the structure and improves the conceptual flow. Second, it adds familiar semantic information to an ER diagram. For this interactive assignment, · Explain when we consider using subtypes. · Create an ER diagram that depicts a superclass (entity: Person) and subclass (entities: Faculty, Staff, Student). Make sure to include at least three attributes for each entity. For instance, the STUDENT subclass has attributes such as MajorDept, Class, and GPA. Use the link to create the model Enhanced Entity-Relationship Model (juniata.edu)
Answered 11 days AfterMay 07, 2022

Answer To: Please see attachment, there are two portions.

Sathishkumar answered on May 12 2022
92 Votes
PART 1:
Some of the ER design limitations:
· For relational data only: realise that the object is
to display relationships. Only the relational form is seen in ER diagrams.
· Not for unstructured data: whether the data is specifically delineated into various fields, rows or columns, ER diagrams are likely to be of little use. The same happens to semi-structured data, since only any of the data can be useful.
· Difficulty integrating with an existing database: using ER Templates to interact
with an existing database may be a difficulty due to different architectures.
· Limited constraints and specification
· Loss of material content: any information is missing or obscured in the ER model.
· No representation of data manipulation: It is difficult to show data manipulation in ER model.
· Popular for high level design: ER model is very popular for designing high level design.
Some tips for improving ER model:
· Show...
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