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

Difference between left outer join and right outer join, Difference between...

Difference between LEFT OUTER JOIN and RIGHT OUTER JOIN In left outer join tuples from the left-hand-side relation which do not match any tuple in the right-hand-side relation

Relationship, What is multiple relationship ?

What is multiple relationship ?

Log, what is the need of a log in dbms

what is the need of a log in dbms

For known, What are the function of DBA?

What are the function of DBA?

Which components of the schema architecture proposed by ansi, What are thre...

What are three components of the schema architecture proposed by ANSI/SPARC? The three component schema architecture proposed by ANSI/SPARC is as given below: External sche

Textbook ordering system, Question: Consider the following database rel...

Question: Consider the following database relations for a textbook ordering system used by a college bookshop: Book (b-copy#, bname, ISBN#, author, price, subject) Order (s#

Relational algebra, Relational Algebra is a set of basic operations used to...

Relational Algebra is a set of basic operations used to influence the data in relational model. These operations allow the user to specify basic retrieval request. The result of re

Statistical analysis of data, An important first step to the statistical an...

An important first step to the statistical analysis of data is to "get to know your data".  The following tasks should contribute to this. (a)   To the right of the dataset cons

Backward recovery (undo), Backward Recovery (UNDO): In this system the unco...

Backward Recovery (UNDO): In this system the uncommitted changes made by a transaction to a database are undone.  Instead the system is reset to the last consistent state of databa

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