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

Cube building in dataware housing , 1) Define a job scheduling strategy tha...

1) Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pict

BMIS 351, Ask question #MinimRead Dennis et al. Chapter 6: Minicase 2. Work...

Ask question #MinimRead Dennis et al. Chapter 6: Minicase 2. Work through it and answer the questions. See the attached example. SequenceDiagram.png Based on the structural mod

Locks, Locks: Serialisabilty is just a test whether a given interleaved sch...

Locks: Serialisabilty is just a test whether a given interleaved schedule is ok or has a concurrency related trouble. Though, it does not make sure that the interleaved concurrent

Explain weak and strong entity type, Explain weak and strong entity type ? ...

Explain weak and strong entity type ? Weak and Strong entity type: An entity set which does not have a primary key is referred to as a weak entity set. The existence of a wea

The tools that are available for managing mysql server, Describe the tools ...

Describe the tools that are available for managing MySQL Server. Given below are the tools to manage MySQL server: mysqld - MySQL server daemon. This is used to begain t

Give expression in tuple calculus and domain calculus, Consider the subsequ...

Consider the subsequent relation schemes:  Project (Project#, Project_name, chief_architect)  Employee (Emp#, Empname)  Assigned_To (Project#, Emp#)  Give expression i

What are advantages of using an index and disadvantages, What are the advan...

What are the advantages of by using an index and what are its disadvantages ? In difference, if the search key of a secondary index is not a candidate key, it is not sufficient

What is cardinality ratio, What is Cardinality Ratio? Cardinality Rati...

What is Cardinality Ratio? Cardinality Ratios - The cardinality ratios for relationship kinds specifies the maximum number of relationship instances in which an entity can pa

Sql, sql is relationally complete-justify

sql is relationally complete-justify

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