Define partial key and primary key, Database Management System

Assignment Help:

Define Partial Key and Primary Key

A partial key, also known as discriminator, is the set of attributes which can uniquely identify weak entities that are related to similar owner entity. Primary key is a unique key but not comprise null values. An entity set can comprise at most one primary key.


Related Discussions:- Define partial key and primary key

Define query by example, Define Query by Example QBE is a query languag...

Define Query by Example QBE is a query language relies upon domain calculus and has two dimensional syntax. The queries are written in the horizontal and vertical dimensions of

Explain the terms data warehousing and data mining, Question: i) Explai...

Question: i) Explain the terms data warehousing and data mining. ii) Discuss the importance of the following security principles that a digital firm should amongst others, n

Why does a dbms query language is designed, Why does a DBMS query language ...

Why does a DBMS query language is designed? A DBMS query language is designed to support end users who use English-like commands. support in the development of complex applicat

Schema, difference between internal schema and external schema in DBMS

difference between internal schema and external schema in DBMS

What is the use of rename operation, What is the use of rename operation? ...

What is the use of rename operation? Rename operation is used to rename both relations and an attributes. It uses the as clause, taking the form: Old-name as new-name.

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

Define mysql_fetch_object(), What are the differences among MySQL_fetch_arr...

What are the differences among MySQL_fetch_array(), MySQL_fetch_object(), MySQL_fetch_row()? Mysql_fetch_object returns the result from the database like objects while mysql

What do you understand by acid, What do you understand by ACID? - ACID...

What do you understand by ACID? - ACID (Atomicity Consistency Isolation Durability) is a quality sought after in a reliable database. Here's the relevance of each quality:

Database Management System, Assume that you are responsible for selecting a...

Assume that you are responsible for selecting a new DBMS product for Sohar Hospital

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