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

What is data independence, What is data independence? Data Independenc...

What is data independence? Data Independence: Techniques which permit data to be changed without affecting the applications in which procedure it. There are two types of data

State the terms designing the database and normalization, State the terms D...

State the terms Designing the database and Normalization Designing the database: Out of the ERD we have formed, it is very easy to verify the tables, the attributes which the

Domain constraints, Domain Constraints Domain constraints are primarily...

Domain Constraints Domain constraints are primarily formed for defining the logically correct values for an attribute of a relation. The relation allows attributes of a relatio

Describe a technique for direct search, Describe a technique for direct sea...

Describe a technique for direct search? Explain how data is stored within a file so which direct searching can be performed. For a file of unordered fixed length records by u

File Management Principles, What are the requirements to ensure the objecti...

What are the requirements to ensure the objectives of file management principle is realized?

Explain the shadow paging recovery technique, Explain the shadow paging rec...

Explain the shadow paging recovery technique.  Ans: Shadow paging is a method used to acquire atomic and durable transactions, and provides the capability to manipulate pages i

Determine the objectives of object oriented design, Determine the Objective...

Determine the Objectives of object oriented design provide an overview of object oriented design; partitioning system to subsystems; describe how a software desig

Explain algorithm of er to relational mapping, Explain algorithm of ER To R...

Explain algorithm of ER To Relational Mapping ? ER-to-Relational Mapping Algorithm: 1) Step 1: Mapping of regular entity types: For each strong entity type E, form a relatio

Software failures-database recovery and security, Software failures :  In s...

Software failures :  In such cases, a software error abruptly stops the implementation of the current transaction (or all transactions), therefore leading to losing the state of pr

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