Domain constraints, Database Management System

Assignment Help:

Domain Constraints

Domain constraints are primarily formed for defining the logically correct values for an attribute of a relation. The relation allows attributes of a relation to be confined to a range of values, for instance, values of an attribute age can be restricted as Zero to 150 or a definite type like integers, etc.

                                                      REDUNDANCY AND ASSOCIATED PROBLEMS

Let us take the subsequent relation STUDENT

Enrolment no

Sname

Address

Cno

Cname

Instructor

Office

050112345

Rahul

D-27, main Road

Ranchi

MCS-011

Problem

Solution

Nayan

Kumar

102

050112345

Rahul

D-27, Main Road

Ranchi

MCS-012

Computer

Organisation

Anurag

Sharma

105

050112345

Rahul

D-27, Main Road

Ranchi

MCS-014

SSAD

Preeti

Anand

103

050111341

Aparna

B-III, Gurgaon

MCS-014

SSAD

Preeti

Anand

103

                                                                           Figure: A state of STUDENT relation

The above relation satisfies the properties of a relation and is said to be in first normal form (or 1NF). Theoretically it is convenient to have all the information in one relation as it is then likely to be simpler to query the database. But the relation over has the following undesirable kinds:


Related Discussions:- Domain constraints

The external or view level in dbms, The External or View Level The ex...

The External or View Level The external or view level is the highest level of abstraction of database. It gives a window on the conceptual view, which permits the user to see

Oracle RDBMS, compare the features of oracle RDBMS with MySQL and Microsoft...

compare the features of oracle RDBMS with MySQL and Microsoft SQL server

ERD, entity relationship diagram about finance

entity relationship diagram about finance

Describe relational model, Describe relational model? Structure of rela...

Describe relational model? Structure of relational data base Basic structure Database schema Keys Schema diagram Query languages

Explain the concept of deadlock, Explain the concept of deadlock Yes. I...

Explain the concept of deadlock Yes. It can direct to deadlock. Suppose that a batch of frames arrived correctly and were accepted. Then receiver will advance its window. Now s

E-r diagram, Let us now make the E-R diagram for the student database as pe...

Let us now make the E-R diagram for the student database as per the explanation given in the previous section. We can also states the overall logical structure of a database usi

Express types of information available in mysql, Express types of informati...

Express types of information available in MySQL? Information as regards the result of queries:  This includes number of records affected by any SELECT or UPDATE or DELETE st

N-ary relationship, For every n-ary relationship type R where n>2, we make ...

For every n-ary relationship type R where n>2, we make a new table S to represent R. We contain as foreign key attributes in s the primary keys of the relations that show the parti

Discuss on transmission impairments, Question 1 Discuss on transmission im...

Question 1 Discuss on transmission impairments Question 2 What is framing? Question 3 Write a note on 10Base2 10Base- T Question 4 Explain the rev

Explain displaying an er schema as an er diagram, Explain the conventions f...

Explain the conventions for displaying an ER schema as an ER diagram? An E-R Diagram scheme might describe certain constraints to that the contents of a database must conform.

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