What are the types of reference, Database Management System

Assignment Help:

What are the types of reference?explain it with suitable examples?

Object oriented language given the ability to refer the object attribute of the type can be referred to the specified type. We can describe the type dept with a field name and a field head which is reference to the type person and a table dept of the type dept as followed

Create type dept(

Name varchar(20),

Head ref(person)scope people

)

Create table dept of dept

The table definition must state that the reverence is derived and must still state a self referential attribute name. When interesting a tuple for dept we can then use

Insert into dept

Values('CS','john')

 


Related Discussions:- What are the types of reference

Explain the utilities which help the dba to manage database, Explain the ut...

Explain the utilities which help the DBA to manage the database? Every DBA uses database utilities to maintain and control their databases. But there is a lot of confusion wit

Hangman, a method named WonGame that checks each letter in the word is matc...

a method named WonGame that checks each letter in the word is matched by its label

Data replication, Data Replication "If a relation R has its copies kept...

Data Replication "If a relation R has its copies kept at two or more sites, then it is considered replicated". But why do we replicate a relation? There are several advan

Define weak and strong entity sets, Define weak and strong entity sets? ...

Define weak and strong entity sets? Weak entity set: entity set that do not have key attribute of their own are known as weak entity sets. Strong entity set: Entity set that

Strong entity set and weak entity set, Strong entity set and weak entity se...

Strong entity set and weak entity set? Strong entity set and weak entity set: A strong entity set has a primary key. All tuples in the set are distinguishable through that key.

Explain the steps for reduction of e-r model, Explain the steps for reducti...

Explain the steps for reduction of E-R model into relational model. Ans:(a) Entity set in E-R model will be considered as table name in relational Model. (b) Attributes of e

How many types of data independence have, Types of data independence D...

Types of data independence Data independence can be classified into the following two types: Physical Data Independence: This means that for any change made in the physi

Logical entity relationship diagrams, How can i turn a conceptual entity re...

How can i turn a conceptual entity relationship diagram into a logical entity relationship diagram? what do i have to do with "mandetory or" and "optional or" relationships?

Describe the term- state diagram, Describe the term- State Diagram Sta...

Describe the term- State Diagram State Diagram: An object could receive a sequence of the input instructions. The state of the object can differ depending upon sequence of in

Characteristics, what are the main characteristics of database

what are the main characteristics of database

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