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

Problem about data mining for business intelligence, Do the 11.1 11.1 Cre...

Do the 11.1 11.1 Credit Card Use. Consider the following hypothetical bank data on consumers’ use of credit card credit facilities in Table 11.3. Create a small worksheet in Exce

Which component is not included in database environment, Which component is...

Which component is not included in database environment ? A users component is not included in database environment.

Oracle, Extend your CREATE TABLE statement from problem 3 with referential ...

Extend your CREATE TABLE statement from problem 3 with referential integrity constraints. Updates and deletes on related rows are restricted. 6. From examination of the sample data

Describes the several relationship constraints, Describes the several relat...

Describes the several relationship constraints through giving suitable example? Constraints on relationships: There are two kinds of constraints on relationships. 1) Mapping

Explain generalization and aggregation in e_r diagram, Explain the concept ...

Explain the concept of generalization and aggregation in E_R diagrams. Give one example for each one of them? Generalization: Consider extending the entity set account throug

Describe the types of attributes, Describe the types of attributes? Ty...

Describe the types of attributes? Types of attributes: An attribute's category determines the type of values that are permitted in the attribute. For instance, the value vers

Explain the systems development life cycle, Explain the systems development...

Explain the systems development life cycle. This is the traditional method to develop, maintain, and replace information systems that contains the project identification and se

Creation of indexes, Creation of Indexes Automatically: When a primar...

Creation of Indexes Automatically: When a primary key or Unique constraint is show in a table definition then a unique index is formed automatically. Manually: User can

#cursor, #what is cursor its uses ? Explain it

#what is cursor its uses ? Explain it

What is association, What is association? Give an example of association ...

What is association? Give an example of association Association is used for establishing relationships among classes. Association describe links among/between classes. For exa

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