Entities:-

"An Entities is any Object, Place, person or Activity about which the data is recorded."

Types of Entities:-

• Dependent Entities:-

        "Depends on another entity for Existence is also called as a Weak Entities."

• Independent Entities:-

              "Its Doesn't depends on any other entity for existence."
        "It is also called Regular Entities."

A Relationship depicts as a diamond Diagram Box.
There are Four Types of Relationship:-

1. One to One
2. One to Many
3. Many To One
4. Many to Many

One to One:- Means One Entities Depends on One Relationship
Ex:- Student & Student Id & Department
In Example One Student have One Student Id and One Department.
One To Many:-Means One Entities Depends on many Relationship.
Ex:- Student & Make Projects, Developer & Developed projects
In this Example One Student have One and More project make and Developer Developed More Projects
Many to One:-Means many Entities Depends on one relationship.
Ex:-Student & Course
In example many Student Enroll in One Course.
Many to Many:-

Three Types of Record based Logical Mode:-

• Hierarchical Mode:- "Represents data in the data of a Tree and Relationship between the data by links."

• Network Mode:- "It is a Similar Hierarchical model."

                                    "Represent record in database Graphically."

• Relation Model:-"Represent data in the Form of Table in a database

              "It is popular model."