Entity identifier key attributes, Database Management System

Assignment Help:

An entity type usually has an attribute whose values are distinct for every individual entity in the collection. Such an attribute is known as a key attribute and its values can be used to recognize each entity uniquely.

Strong entity set: The entity types having a key attribute are known as strong entity types or regular entity types.

  • EXAMPLE: The Student entity has a key attribute RollNo which uniquely recognized it, hence is a strong entity.

Attributes

Let us first answer the question:

What is an attribute?

An attribute is a property used to define the specific feature of the entity. So to define an entity entirely, a set of attributes is used.

For example, a student entity may be defined by the student's name, address, age, course, etc.

An entity will have a value for every of its attributes. For example for a specific student the following values can be assigned:

RollNo: 1234

Name: Supriya

Age: 18

Address: B-4, Mayapuri, Delhi. Course: B.Sc. (H)


Related Discussions:- Entity identifier key attributes

Describe the association - design, Describe the Association: Design  ...

Describe the Association: Design  Before we describe association design let us define association "Association is set of links between two objects in the object model". It is

List any eight applications of dbms, List any eight applications of DBMS. ...

List any eight applications of DBMS. a) Universities b) Airlines c) Banking d) Credit card transactions e) Tele communication f) Sales g)Finance h) Manufac

Describe integrity constraints, Describe integrity constraints? Integr...

Describe integrity constraints? Integrity Constraints - A database is just as excellent as the information stored in it, and a DBMS must therefore help avoid the entry of inc

Update operations, The Update Operations : Update operations are used fo...

The Update Operations : Update operations are used for altering database values. The constraint violations faced by this operation are logically the similar as the problem faced

What is middleware, Question: a) What is Client/Server and what benefit...

Question: a) What is Client/Server and what benefits can be expected from Client/Server systems? b) Explain what middleware is and what it does. Why would MIS managers be p

Give the limitations of sql authorization, Give the limitations of SQL auth...

Give the limitations of SQL authorization. The code for checking authorization becomes intermixed with the rest of the application code. Implementing authorization by applic

Develop motel point of sale software, Project Description: I need a poin...

Project Description: I need a point of sale for motels. It needs to run on windows and requires being network able so that we can have more than one computer using it at once.

Create table employee and enter employee data in sql, Create table employee...

Create table employee and enter employee data in SQL? Consider the following relational schemas: EMPLOYEE (EMPLOYEE_NAME, STREET, CITY) WORKS (EMPLOYEE_NAME, COMPANYNAME, SAL

What is abstraction, What is abstraction? Abstraction in the object ori...

What is abstraction? Abstraction in the object orientation is a idea that provide opportunity to express necessary properties of object without providing much details of the im

Speedup query processing, Speedup Query Processing: A query that includes d...

Speedup Query Processing: A query that includes data at various sites can be split into sub-queries. These sub- queries can be implemented in parallel by various sites. Such parall

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd