Data Modeling and its Relation to Entity Relationship Approach

advanced database and applications
Data Modeling and its Relation to Entity Relationship Approach
SEPTEMBER 10, 2018

Table of Contents
1.0 Introduction.........................................................................................................................................2
2.0 Data Modelling Using the Concept of the ER Approach..................................................................3
3.0 Data Modeling in DB design...............................................................................................................4
3.1 Data Model Components.................................................................................................................5
3.2 Importance of Data modeling.........................................................................................................5
3.3 ER Model..........................................................................................................................................6
Constructs of Entity Relationship Model.........................................................................................6
External model...................................................................................................................................10
Conceptual Models............................................................................................................................10
3.4 Relational Model............................................................................................................................10
Mapping Entity................................................................................................................................12
Mapping the Relationship...............................................................................................................12
Mapping the Weak Entity sets........................................................................................................13
Mapping the Hierarchical Entities.................................................................................................14
4.0 Benefits of Data Models.....................................................................................................................15
Conclusion................................................................................................................................................16
List of References....................................................................................................................................17
Content of tables and Figures
Figure 1 table relation.......................................................................................................................11
Figure 2 Example of an Entity diagram............................................................................................12
Figure 3 mapping the relationship....................................................................................................13
Figure 4 Explanation of weak entity.................................................................................................14
Figure 5Mapping the Hierarchical Entities......................................................................................15

1.0 Introduction
In the modern era, data storage has been considered as a very critical area and that needs to be
taken care of in a very serious manner. The reason to as why database exists is for helping in
storage. The advancements of such technology has really helped in creation of databases, thus
helping us to save our files in the machines, servers and even in the cloud. The urge to have a
good database for the storage of information belonging to any given company or an organization
or even to an individual has led to many seeking the databases services or applications available
in the market. Database can be defined as the data structure that is used to store organized and
ordered information [1]. Many database systems are known for them consisting of multiple
tables where each table may have different fields and records. A good example is the database of
a company that may have the following tables respectively; Employee Table, Financial Records
table and the Products table where each table may have other different fields that are so much
relevant to the information that is to be stored in the table.
The definition of a database comes from the file systems where it is defined as the concept of
gathering of information. In this topic it is defined as data which must be stored in a server. In
this concept the data is ordered and organized in a manner that it will be easily retrieved, easily
managed and much more edited in many ways may be significant to the end user [2]. It will be
good to understand that when one is using a DB, data will not be stored in the hard drive of the
computer but it will be stored in the cloud on remote server located somewhere. The application
of a DDMS will be applied in accessing or when in need to retrieve the information where one
must query or call a given function or command for a certain retrieval. In a database the data
required to be stored will be stored on how it is related to each other, where it takes the form of
tables that are made of columns also known as fields and rows which are also known as

records(items). The most common language that is used for querying and managing the
databases which are relational is referred to as Structured Query Language (SQL) [3].
In this concept of study about advanced database and applications the topic to be covered will be
data modelling and the relationship it has with the Entity relationship approach. At the end of the
concept one is supposed to have an idea to what are some of the basic concepts of Entity
Relationship Model, the data model components, the constructs for the entity relationship
modeling, the database design process and its parts such as the data modeling, the steps used in
building the data model and lastly is the understanding of how to develop a basic schema.
2.0 Data Modelling Using the Concept of the ER Approach
In the definition of a data model it is stated as the data structure conceptual representation that is
always needed by a DB. The constructions in the data or data structures consists of:
The data objects
The association among and between the related data objects
The rules which are used for governing all the operations with regards to the related
objects
The concept in the data model is not how the data is used or organized rather than how the
operations are performed on the specified related data [4]. Data model is always liberated of the
software constraints and those of the hardware. The main idea of data model is presenting the
data to the user as it is seen in the real world. This has made it to become essence in serving as
the interface between all the notions making up the events in the real world, processes and the
physical representation of the database concepts [5]. There are two main methods that are