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

Transaction, what are the states of transaction?

what are the states of transaction?

Explain query execution plan, Explain query execution plan? - Optimizer...

Explain query execution plan? - Optimizer available in SQL Server optimizes code to be effectively executed. - A query execution plan demonstrates how this optimizer would r

Single and multi valued attributes, Attributes having a one value for a par...

Attributes having a one value for a particular entity. For instance, Age is a single valued attribute of a student entity. Attributes  that  have  more  than  single  values

How do you find the final model after iterative analysis, How do you find t...

How do you find the final model after iterative analysis? Why is iterative analysis of any of the problem needed? The final model serves as the base for system architectur

Explain the dynamic hashing techniques, Explain the Dynamic Hashing Techniq...

Explain the Dynamic Hashing Techniques There are two methods in it: extendible hashing - stores an access structure in addition to the file, and therefore is somewhat identica

Data storage and retrieval services, An Enterprising group of Entrepreneurs...

An Enterprising group of Entrepreneurs introduced a new business named StoreItRite which is based on data storage and retrieval services. It provides the services and the company c

Create a database, The database will enable college administrators the abil...

The database will enable college administrators the ability to track students initial major. This will help college officials decide how best to prepare students for their goals an

Which file organization provides very fast access, Which file organization ...

Which file organization provides very fast access to any arbitrary record of a file? Hashed file organization provides very fast access to any arbitrary record of a file.

Windows 8 Administrative Tools, Which two tools are used to administer user...

Which two tools are used to administer users for Active Directory?

RDM & ER Modelling, #questiRegional Gardens has many nurseries, including W...

#questiRegional Gardens has many nurseries, including Wagga Wagga, Bathurst, Albury, Orange, and Dubbo. Each nursery is known by its campus code, eg WW, B, A, O and D respectively.

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