What is inheritance, Database Management System

Assignment Help:

What is inheritance? Define it in detail?

 Inheritance

Inheritance can be at the levels of types, or at the level of tables we first consider inheritance of types, then inheritance at the level of labels.

Type inheritance

Assume that we have the following type definition for people

create type person

(name varchar(20)

address varchar(20))

Table inheritance

Create table people of person

The consistency requirements for sub tables are

1. Each tuple of the sub table can correspond to at most single tuple in each of its immediate sub tables.

2. SQL:1999 has an additional constraint that all the tuples corresponding to each other must be derived from single tuple .

 


Related Discussions:- What is inheritance

Create an entity relationship diagram, Create an entity relationship diagra...

Create an entity relationship diagram, Database Management System

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

Generalization and specialization, design a generalization specialization h...

design a generalization specialization hierarchy for a motor vehicle sales company. the company sells motorcycles, passenger cars, vens and buses.

Natural join-table handling, Natural Join : It is the similar like Equi joi...

Natural Join : It is the similar like Equi join except one of the duplicate columns is removed in the result table. The natural join is the most usually used form of join operation

What are the various states of transaction process, What are the various st...

What are the various states through which a transaction passes through in its lifetime?  Briefly discuss all the events that causes transition from one state to another.   Ans:

Private Tuition, Hi, Do you offer private tuition for DBMS?

Hi, Do you offer private tuition for DBMS?

ERD, The entity type STUDENT has the following attributes: Student Name, Ad...

The entity type STUDENT has the following attributes: Student Name, Address, Phone, Age, Activity, and No of Years. Activity represents some campus-based student activity, and No o

What is dml query langauge, What is DML Query Langauge? Data Manipulati...

What is DML Query Langauge? Data Manipulation Language (DML) - A data manipulation language is a language in which enables users to access or manipulate data as organized throu

Illustrate how customer relationship is promoted, FitAll Ltd is a company t...

FitAll Ltd is a company that manufactures clothes. Its processes are manual and there are stand-alone Information Systems that aid to manage them. The Information Systems were purc

Explain the internal architecture of 8086, Problem 1. Write an assembly...

Problem 1. Write an assembly program to find the smallest among two numbers Writing an assembly program to find the smallest among two numbers 2. Explain the intern

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