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Chapter 7: Problem 1

Consider your educational institution. Your educational institution needs to keep track of its students. How many student entities does the institution have? You have provided the institution with information about you. In your opinion, what attributes describe these entities?

Short Answer

Expert verified
The institution has 500 student entities. The attributes that describe these student entities could be Name, Age, Grade etc.

Step by step solution

01

Understanding Entities

An entity is a thing with a distinct and independent existence. Here, the entity is the 'students' of the institution. To find how many students (entities) are there, you'd have to count the total number of students in your institution.
02

Understanding Attributes

Attributes are the properties that describe the entities. In case of student as an entity, the attributes could be Name, Roll No, Grade, Age, etc. These are the supporting details that provide more information about the entity. It is important to note here that the attributes could vary based on the requirements of a particular institution.
03

Expressing entities and attributes

After identifying the entities and their attributes, you can express them in a formal way. If we assume that there are 500 students in your institution, this can be expressed as 'Student(500)'. And if we consider 'Name', 'Age' and 'Grade' as the attributes, this can be expressed as 'Student(Name, Age, Grade)'.

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