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 do you understand by raid, What do you understand by RAID? Explain RA...

What do you understand by RAID? Explain RAID Level 4 and Level5? RAID - It is stands for Redundant Array of Inexpensive Disks (as named by the inventor), or alternatively Re

Data analysis and design, give some example real-life situations where DBMS...

give some example real-life situations where DBMS are most suiitabe

What is the use of raid, What is the use of RAID? A variety of disk-org...

What is the use of RAID? A variety of disk-organization methods, collectively called redundant arrays of independent disks are used to better the performance and reliability.

What is data defination language, What is DDL? Make a list of commands with...

What is DDL? Make a list of commands with short description used in DDL Ans: Data Definition Language that is abbreviated as DDL is a computer language for defining data struct

What is known as clustering file organization, What is known as clustering ...

What is known as clustering file organization? In the clustering file organization, records of several dissimilar relations are stored in the similar file.

Describe entity referential integrity and integrity, Describe entity refere...

Describe entity referential integrity and integrity. Give an example of each. Entity Integrity Rule - If there is a attribute A of relation R is a prime attribute of R then A

Unnormalize form, employee(empid,empname,dept,telno,mobno, add,sssno,tinno,...

employee(empid,empname,dept,telno,mobno, add,sssno,tinno,WEdates,WEcomp,WEadd,WEpos,WEres) this is a employee record which is need to be normalize.the WE means work experience

Physical database design issues, Physical Database Design Issues The da...

Physical Database Design Issues The database design includes the process of logical design with the use of E-R diagram, normalisation, etc., followed by the physical design.

Determine the method of choosing algorithms, Determine the method of Choosi...

Determine the method of Choosing Algorithms In general, most of operations are easy and have a satisfactory algorithm since description of what is to be done also shows how i

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