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 retrieval in qbe, Explain retrieval in QBE? Retrieval in QBE : ...

Explain retrieval in QBE? Retrieval in QBE : A "GUI" for expressing queries. Based on the Domain Relational Calculus (DRC) Actually invented before GUIs. Very co

Define first normal form and second normal form, First Normal Form and seco...

First Normal Form and second normal form First Normal Form (1NF) A relation is said to be in 1NF if it having no non-atomic values and each row can give a unique combinat

Multivalued attributes, For every multivalued attribute 'A', we make a new ...

For every multivalued attribute 'A', we make a new relation R that contains an attribute corresponding to plus the primary key attribute k of the relation that shows the entity typ

Inheritance, what is relationship inheritance and attribute inheritance

what is relationship inheritance and attribute inheritance

What is the difference between where and having clauses, What is the differ...

What is the difference between WHERE and HAVING clauses?. Predicates in the WHERE clause applies to every tuple while the predicate in the HAVING clause applies to groups.

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

Domains, A domain is a set of permissible values that can be given to an at...

A domain is a set of permissible values that can be given to an attribute. So each attribute in a table has a definite domain. Values to these attributes cannot be assigned outside

What is a database, What is a database? Database - Basically in simpl...

What is a database? Database - Basically in simple terms A database is a collection of inter related data and/or information stored so which it is available to several users

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