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

Entity set that does not have sufficient attributes known as, An entity set...

An entity set that does not have sufficient attributes to form a primary key is called? An entity set that doesn't have sufficient attribute to form a primary key is known as w

Need for client server computing, Need for Client Server Computing- Client/...

Need for Client Server Computing- Client/Server (C/S) architecture includes running the application on multiple machines in which every machine with its component software tackles

State the design of associations, State the Design of Associations Bef...

State the Design of Associations Before designing associations, it is essential to know the way they are used. For this, analysis of association traversals is required. It is

Mention the purpose of sid and sod lines, Mention the purpose of SID and SO...

Mention the purpose of SID and SOD lines SID (Serial input data line): It is an input line by which the microprocessor accepts serial data. SOD (Serial output data line)

Create a technology web server, Database design Database tables will be...

Database design Database tables will be created for you on the Technology web server. The schema will be as follows. Please note that this is a simplified database structure, d

Having clause with sub queries, Having Clause with sub queries: First we h...

Having Clause with sub queries: First we have to recollect the GROUP BYclause. The following query searches the minimum salary in every department. SELECT DEPTNO, MIN (SAL)

Which language has recently become the defacto standard, Which language has...

Which language has presently become the defacto standard for interfacing application programs along with relational database system? The language which has recently become the

Illustrate the fifth normal form, Fifth Normal Form (5NF) These relatio...

Fifth Normal Form (5NF) These relations still have a difficulty. While defining the 4NF we mentioned that all the attributes depend upon each other. Whereas creating the two ta

Subclassing, In the ER diagram, one example of subclassing is depicted foll...

In the ER diagram, one example of subclassing is depicted following the Services entity. The subclasses Item Based and Time Based are created. The entity Services gains the attribu

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