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Introduction
◦ Process of creating a data model for an information system by
applying formal data modeling techniques.
◦ Process used to define and analyze data requirements needed
to support the business processes.
◦ Therefore, the process of data modeling involves professional
data modelers working closely with business stakeholders, as
well as potential users of the information system[1].

What is Data Model
◦ Data Model is a collection of conceptual tools for describing data,
data relationships, data semantics and consistency constraint.
◦ A data model is a conceptual representation of data structures
required for data base and is very powerful in expressing and
communicating the business requirements
◦ A data model visually represents the nature of data, business rules
governing the data, and how it will be organized in the database

◦ A data model provides a way to describe the design of
a database at the physical, logical and view levels.
◦ There are three different types of data models
produced while progressing from requirements to the
actual database to be used for the information
system[2].
What is Data Model

◦ Conceptual: describes WHAT the system contains
◦ Logical: describes HOW the system will be implemented,
regardless of the DBMS
◦ Physical: describes HOW the system will be implemented using a
specific DBMS [3]
Different Data Models

A data model consists of entities related to each other on a diagram:

Example:
Given that …
◦ “Customer” is an entity.
◦ “Product” is an entity.
◦ For a “Customer” we need to know their “customer number” attribute
and “name” attribute.
◦ For a “Product” we need to know the “product name” attribute and
“price” attribute.
◦ “Sale” is an entity that is used to record the interaction of “Customer” and
“Product”.

Here is the diagram that encapsulates these rules:

• If we want to know the price of a Sale, we can ‘find’ it by
using the “Product Code” on the instance of “Sale” we are
interested in and look up the corresponding “Price” on the
“Product” entity with the matching “Product Code”.

Types of Data Models
◦ Entity-Relationship (E-R) Models
◦ UML (unified modeling language)

Entity-
Relationship
Model
◦ Entity Relationship Diagrams (ERD) as this is
the most widely used
◦ ERDs have an advantage in that they are
capable of being normalized
◦ Represent entities as rectangles
UniversityStudent
PK StudentID
StudentName
StudentDOB
StudentAge
Entity
Attributes
Primary key

Why and When
◦ The purpose of a data model is to describe the concepts
relevant to a domain, the relationships between those
concepts, and information associated with them

◦ Used to model data in a standard, consistent, predictable
manner in order to manage it as a resource.
◦ To have a clear picture of the base data that your business
needs
◦ To identify missing and redundant base data [4].
Why and When

◦ To Establish a baseline for communication across
functional boundaries within your organization
◦ Provides a basis for defining business rules
◦ Makes it cheaper, easier, and faster to upgrade your IT
solutions[5].
Why and When

References
◦ [1] Pedersen, Torben Bach, and Christian S. Jensen. "Multidimensional data modeling for
complex data." Proceedings 15th International Conference on Data Engineering (Cat. No.
99CB36337). IEEE, 1999.
◦ [2] Kitchenham, Barbara A., Robert T. Hughes, and Stephen G. Linkman. "Modeling
software measurement data." IEEE Transactions on Software Engineering 27.9 (2001): 788-
804.
◦ [3] Chebotko, Artem, Andrey Kashlev, and Shiyong Lu. "A big data modeling methodology
for Apache Cassandra." 2015 IEEE International Congress on Big Data. IEEE, 2015.
◦ [4] Peckham, Joan, and Fred Maryanski. "Semantic data models." ACM Computing Surveys
(CSUR) 20.3 (1988): 153-189.
◦ [5] Lv, Zhihan, et al. "Next-generation big data analytics: State of the art, challenges, and
future research topics." IEEE Transactions on Industrial Informatics 13.4 (2017): 1891-1899.

data modelingEntity-Relationship (E-R) Models UML (unified modeling language).pptx

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