What are partial and natural key, Database Management System

Assignment Help:

What are partial, alternate,, artificial, compound and natural key?

Partial Key: It is a set of attributes that can uniquely recognize weak entities and that are related to same owner entity. It is sometime known as Discriminator.

Alternate Key: All Candidate Keys excluding the Primary Key are called as Alternate Keys.

Artificial Key: If no obvious key either stands alone or compound is available, then the last resort is to simply make a key, by assigning a unique number to every record or occurrence. Then this is known as developing an artificial key.

Compound Key: If no single data element uniquely identifies occurrences within a construct, then combining multiple elements to make a unique identifier for the construct is known as creating a compound key.

Natural Key: When one of the data elements stored within a construct is utilized as the primary key, then it is known as the natural key.

 


Related Discussions:- What are partial and natural key

Explain the cartesian product, Explain the Cartesian product:  The Cart...

Explain the Cartesian product:  The Cartesian product operation does not need relations to union-compatible.  The meaning of this is that the involved relations may have dissim

Ddl compiler-database management system, DDL Compiler The DDL compile...

DDL Compiler The DDL compiler changes the data definition statements (such as CREATE TABLE .... in SQL) into a set of tables having metadata tables. These tables have infor

Management information system, management information system based on funct...

management information system based on functional organisation

In the architecture of a database system which external leve, In the archit...

In the architecture of a database system which external level used? In the architecture of a database system view external level used.

Oracle/sql, can you create a database for me in oracle/sql

can you create a database for me in oracle/sql

ERD, A student entity type has the following attributes,name..

A student entity type has the following attributes,name..

Define the notation for classes and atrributes, Define the notation for cla...

Define the notation for classes and atrributes The notation for class, attribute, and operations are shown below:     Figure: Class with attributes and operations A

Define deadlock recovery measures, Define Deadlock recovery measures       ...

Define Deadlock recovery measures                   To recover from deadlock, the cycle in the wait-for-graph should be broken. The common technique of doing this is to rollbac

Describe the types of inheritance, Describe the types of Inheritance ...

Describe the types of Inheritance 1.  Single inheritance 2.  Multiple inheritance 3.  Hierarchical inheritance 4.  Multilevel inheritance

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