Domains, Database Management System

Assignment Help:

A domain is a set of permissible values that can be given to an attribute. So each attribute in a table has a definite domain. Values to these attributes cannot be assigned outside their domains.

In the example given above if domain of PERSON_ID is a set of integer values from 1 to

1000 than a value outside this range will not be valid. Many other common domains may be age between 1 and 150. The domain can be definite by assigning a type or a format or a range to an attribute. For instance, a domain for a number 501 to 999 can be particular by having a 3-digit number format having a range of values between 501 and 999. Therefore, please note the domains can also be non-contiguous. For instance, the enrolment number of IGNOU has the last digit as the check digit, therefore the nine- digit enrolment numbers are non continuous.


Related Discussions:- Domains

Improved availability, Improved availability: The data in a distributed sys...

Improved availability: The data in a distributed system may be replicated so that it is at more than one site. Thus, the failure of a node or a communication link does not necessar

Assignments, i have assignments I don''t have time to finish because of wo...

i have assignments I don''t have time to finish because of work and other assignments, can you help with this? All are from the book Darabase design, application development and a

What are the properties of transaction, What are the properties of transact...

What are the properties of transaction? There are three properties of transactions :- A)     Atomicity B)      Consistency C)       Isolation

The maximum no of key fields that can be used in a header, The Maximum no o...

The Maximum no of key fields that can be used in a header is?? 50

Types of locks, Types of Locks There are two necessary types of locks: ...

Types of Locks There are two necessary types of locks: Binary lock : This locking mechanism has two states for to a data item: locked or unlocked Multiple-mode loc

Designing a Human Resources Database LASA1, Scenario: You are a freelance ...

Scenario: You are a freelance database designer who has just been contacted by a small software development company named Altair Software. The president of the company has asked

Sequences-data control, Sequences Sequences: Automatically produ...

Sequences Sequences: Automatically produce unique numbers Are sharable Are typically used to make a primary key value Replace application code Speed up t

What are the reasons of bucket overflow, What are the reasons of bucket ove...

What are the reasons of bucket overflow? Explain any two methods for solving this problem. Ans:  It is general for file structures to be divided into equal-length partitions, k

Describe the concepts of structural semantic data model, Question 1 List a...

Question 1 List and explain various Normal Forms. How BCNF differs from the Third Normal Form and 4th Normal forms? Question 2 Describe the concepts of Structural Semantic Da

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