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

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

Create a database, Project: Microsoft Access You have been asked by the ...

Project: Microsoft Access You have been asked by the ABC Tanning Salon to create a database that can be used to track the salon's customers.  You are to create a table in Access

Primary interface between a visual basic application, Question (a) Visu...

Question (a) Visual Basic is governed by an event processor. Explain the meaning of this phrase. (b) Differentiate between an general procedure and event procedure. (c)

What is the difference between serial and sequential files, What is the dif...

What is the difference between serial and sequential files? How searching is applied on both?    Ans: A serial file is one where the records have been stored in the order where

What is the difference between a key and a superkey, What is the difference...

What is the difference between a key and a superkey? Key - A key a single attribute or a combination of two or more attributes of an entity set which is used to identify one

Illustrate about the advanced object design, Illustrate about the advanced ...

Illustrate about the advanced object design Advanced object design is a complex task. The objects discovered through analysis serve as a skeleton of design. The operations reco

Cartisian product, Explain the cartesian product in Database Management Sys...

Explain the cartesian product in Database Management System

Define the categories of sql statements, Define the categories of SQL State...

Define the categories of SQL Statements? 1) Statements that don't return a result set. This statement class includes INSERT, DELETE, and UPDATE. 2)Statements that return

What are object interaction diagrams, What are object interaction diagrams?...

What are object interaction diagrams? Object interaction diagrams are the diagrams that used to describe order in which messages are communicated in execution of an operation,

Development of an ER diagram and database implementation, i want answers th...

i want answers this assignment now if yiu can maket for me now ?

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