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 the use of a slotted-page structure, What is the use of a slotted-p...

What is the use of a slotted-page structure and what is the information are there in the header? The slotted-page structure is used for organizing records within a one block.

What are the overlapping elements, What are the Overlapping elements O...

What are the Overlapping elements Overlapping elements can be found by scanning all the elements in front of deleted element in priority list for the sheet and comparing them

What is the function of a domain, What is the function of a Domain? A d...

What is the function of a Domain? A domain defines the technical settings of a table field. A domain describes a value range, which sets the permissible data values for the

Central database schema, Consider an information system designed for an onl...

Consider an information system designed for an online company which provides IT products and services. These include desktops, laptops, networking products, IT books, parts, and te

Define the term e-government, Question: (a) Define the term e-Governme...

Question: (a) Define the term e-Government and briefly explain, using appropriate examples, the aspects it covers. (b) Give four reasons as to why a country should adopt e

Define data conversion, Define data conversion? Helpful to load data in...

Define data conversion? Helpful to load data into temporary staging tables. Then can write SQL code to do much of data processing. SQL code is simpler and faster to write than

Neo4j, I have one assignment that has to be done in neo4j

I have one assignment that has to be done in neo4j

Define average seek time, Define average seek time. The average seek ti...

Define average seek time. The average seek time is the average of the seek times, calculated over a sequence of random requests.

Create table statements for original database, MySQL statements for extendi...

MySQL statements for extending the database to incorporate new facilities Deliverables for submission You must submit the following deliverables in the Assignment Dropbox in

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