Explain nested relations, Database Management System

Assignment Help:

Explain nested relations?

Nested relations

The assumption of INF is a natural one in the bank examples we have considered.

However, not all applications are best modelled by INF relations.

The nested relational model is an extension of the relational model in which domains might be either atomic or relation valued.

We illustrate nested relations by an example from a library. Assume we store for every book the following in formations

 Book title

Set of authors

Publishers

Set of keywords

We can see that if we describe a relation for the preceding information, several domains will be monatomic

Authors

Keywords

Publishers

Complex types

Collection and large object types

Create table books(

...

Keyword-set setoff(varchar(20))

           ...

            )

            Structure types

            Creation of values of complex types

 


Related Discussions:- Explain nested relations

Explain the term- data flows, Explain the term- Data Flows Data Flows:...

Explain the term- Data Flows Data Flows: A data flow connects output of an object or process to input of another process or object. It represents an in-between data value wit

What is advantage of two-way association, What is advantage of two-way asso...

What is advantage of two-way association? Two-way association advantages are following: a) Independent of the classes. b) Useful for existing predefined classes that are

Explain outer join, Explain outer join? Outer Join - If there are any...

Explain outer join? Outer Join - If there are any values in one table which do not have corresponding value(s) in the other, in an equi-join which will not be chosen. Such ro

Organize the clients from email marketing, Function requirement as given: ...

Function requirement as given: 1> manage fans and likes and followings those information from facebook. twitter. google+ and linkedin etc 2> Organize the clients from email m

Using column aliases-data manipulation language, Using Column aliases E...

Using Column aliases Example: To print column names as NAME and ANNUAL SALARY SELECT ENAME "NAME", SAL*12 "ANNUAL SALARY" FROM EMP;

MULTI-LIST FILE ORGANIZATION, sir, could anybody help me in getting complet...

sir, could anybody help me in getting complete information about the mentioned topic

#normalisation.., define normalisation and functional dependency

define normalisation and functional dependency

Define direct file organization, Define Direct file organization? The d...

Define Direct file organization? The direct file organization is employed to enhance the performance in accessing the records than sequential file organization. In direct file

Data Analysis, A buyer for a large department store chain must place orders...

A buyer for a large department store chain must place orders with an athletic shoe manufacturer six months prior to the time the shoes will be sold in the department stores. In par

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