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ER Diagram for Company Database

In DBMS, an ER diagram for a company database shows how the databases are connected. It also shows how all the databases are logically related to each other. We can also create an ER diagram by drawing the figure of a different part of the company database, their properties, and how they perform their task.

We can draw an ER diagram of the company database by drawing the design of the database. The sketch of the database became the storage of the database where the data comes and goes.

Details Company Database ER Diagram:

Now we describe the overall function of the Company database in the below table. It is a complete overview of the information about the company database project.

Name: ER Diagram of the Company Database.
Abstract: The ER Diagram of the company database shows the relationship between various entities. We can also call it the blueprint of the company database.
Diagram: We can also call the ER diagram an Entity Relationship diagram.
Tool used: The ER diagram provides some symbol that is known as the diagramming tool.
Users: The users of the ER diagram are admin, website, and employee.

What is a Company Database?

The company database is a database that contains all the information about the company and its employee. The information includes details about the company's demographic and firmographics details. The firmographic details of the company include the following things.

  • Company name.
  • Address of the head office.
  • The employee strength of the company.
  • Revenue of the company.
  • Industry of the company.
  • The technology used in the company.
  • Link to the company's social media page.
  • Funding-related information of the company.
  • Website of the company.
  • Many other different parameters.

What is an ER Diagram?

We can also call ER diagram the database design for the company database project. The ER diagram is like a picture that contains how all the entities are related to each other. The most important part of the ER diagram is Relationships, Attributes, and Entities.

Importance of ER Diagram

The ER diagram for the project is the foundation for building the project's database. The properties, datatypes, and attributes are defined by the ER diagram.

ER Diagram for Company Database

The ER diagram for the company database, the system data, and their attributes. The data and the attributes are represented by the table, and the table shows how they are related to each other.

Database Design for the Company Database

ER Diagram for Company Database

The above diagram shows the database design for the company database. This database design shows all the system data, and the output for the user ate stored in the database. In DBMS, a good ER diagram is needed for the creation of a company database.

Company Database ER Diagram Tables

The below table shows all about the field name of the table, description, datatype, and character length. Each table of the ER diagram defines and explains the data storage.

The field column lists all the attributes of the database that describes each column. The types table of the database shows what kind of data each attribute is, and the length shows how many characters it has.

Table name: Dependent

Field Description Type Length
Name Name of the dependent Varchar 255
Sex Gender of the dependent Varchar 255
Birth_date Date of birth of the dependent Varchar 255
Relationship Relationship of the company varchar

Table name: Project

Field Description Type Length
Name Name of the project Varchar 255
Budget Budget of the project Int 11
Location Location of the project Varchar 255

Table name: Department

Field Description Type Length
Name Department name varchar 255
location Department location varchar 255

Table name: Employee

Field Description Type Length
First_name First name of employee Varchar 255
Middle_initial Middle name of employee Varchar 255
Last_name Last name of employee Varchar 255
Status Status of employee Varchar 255
Address Address of employee Varchar 255
Salary Salary of the emplyee int 10
Sex Gender of the employee Varchar 255
ssn Seriel number of number Int 10

With the help of the above tables, we can set up the database for the company database. It provides the full description of the database with its table names. They will enter all the values and attributes for the database in the table.

How to Create ER Diagram

We can create the ER diagram for the table just in 5 minutes. There are some steps, and with the help of these steps, we can build the ER diagram for the company database project. The steps are as below.

Step 1:

We have to familiarize ourselves with the entity relationship diagram cardinality and symbols. Then we have to show the data structure for the project in the entity relationship diagram. The symbol of the entity relationship diagram shows how they fit together. Before making the ER diagram, we should properly know the meaning of all the symbols and how to use all of them symbols.

Symbol of Entity Relationship Diagram:

  1. Fields: This entity shows how the different types of data are used together for a project. The symbol is used to show how the part of the project is working.
  2. Key: It is a type of technique that is used to categorize the quality of the data. There are two types of keys available for the database. These are as follows.
    • Primary key: It is a set of unique properties that are used for finding the specific entity.
    • A foreign key: It is a type of key made up of a piece of data with too many links to other things.

Step 2: Finalize the entities included

Start making your ER Diagram by deciding on all the parts your company database must have. You'll need to leave the area in your design for these rectangles to be included later.

Step 3: Add the attributes of each entity

After you've decided on the entities, think about the traits you'll need for each one. In a conceptual ER diagram, the details of the different entities are given as attributes. Attributes are things like a thing's traits, a many-to-many relationship, or a one-to-one relationship. Attributes with multiple values can be given more than one value.

Step 4: Describe the relationships (cardinality) between entities and attributes.

You will need the entities, their attributes, and the relationships between them to plot the relationships between the ERD. To get the right entity relationship diagram, you will use the information you gathered to build the data structure.


You need to know how the company database was designed and built using diagrams. With the help of an ER diagram will help you make a system that works well.

Making it will help you understand how the software works behind the scenes. This is where all the data that goes in and out of the system will be stored.

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