Explain weak and strong entity type, Database Management System

Assignment Help:

Explain weak and strong entity type ?

Weak and Strong entity type: An entity set which does not have a primary key is referred to as a weak entity set. The existence of a weak entity set depends on the existence of a strong entity set; it must associate to the strong set via a on-to-many relationship set. A discriminator of a weak entity set is the set of attributes that distinguishes between all the entities of a weak entity set. The primary key of a weak entity set is formed by the primary key of the strong entity set on that the weak entity set is existence depends, plus the weak entity set's discriminator.


Related Discussions:- Explain weak and strong entity type

Explain the term- periodic recomputation, Explain the term- Periodic recomp...

Explain the term- Periodic recomputation Periodic recomputation:  Base values are often updated in bunches. Sometimes, it is possible to just recompute all derived attributes p

Php optimization on iis 8, Project Description: We have purchased facebo...

Project Description: We have purchased facebook style chat software which we are using with our site. It is prepared in PHP but the rest of the site is developed asp.net. Iss

Fragmentation, let us consider a table having 2200 records and the fixed si...

let us consider a table having 2200 records and the fixed size of the table to be considered as 25.then how many numbers of table is requredto perform horizontal fragmentation

What are the failures of controlling events between objects, What are the f...

What are the failures of Controlling Events Between Objects  Failure Unintentional termination of system. Several possible causes: failure of system hardware, o

Define deadlock prevention, Define deadlock prevention. Deadlock preven...

Define deadlock prevention. Deadlock prevention is a set of methods for ensuring that at least one of the four essential conditions like mutual exclusion, hold and wait, no pre

Give the levels of data abstraction, Give the levels of data abstraction? ...

Give the levels of data abstraction? There are three levels of Data Abstraction a) Physical level b) logical level c) view level

What are stored and derived attributes, What are stored and derived attribu...

What are stored and derived attributes? Stored attributes: The attributes keeps in a data base are known as stored attributes. Derived attributes: The attributes that are de

Job scheduling strategy, 1) Define a job scheduling strategy that will meet...

1) Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pict

Define view? how it is related to data independence, A View may be defi...

A View may be defined of as a virtual table, that is, a table that does not really exist in its own right but is instead inferred from one or more underlying base data table. T

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