Explain weak and strong entity sets, Database Management System

Assignment Help:

Explain weak and strong entity sets?

Weak and Strong entity sets: A physically powerful entity set has a primary key. All tuples in the group are distinguishable through that key. A weak entity set has no primary key unless attributes of the tough entity set on which it depends are included. Tuples in a weak entity grouped are partition according to their relationship along with tuples within a strong entity set. Tuples inside each partition are discernible by a discriminator, that is a set of attributes. A strong entity set has a primary key. All tuples within the set are distinguishable through that key. A weak entity set has no primary key unless attributes of the strong entity set on that it depends are included. Tuples in a weak entity set are partitioned according to their relationship along with tuples in a strong entity set. Tuples within each partition are discernible through a discriminator that is a set of attributes.


Related Discussions:- Explain weak and strong entity sets

Lack of redundancy, Lack of Redundancy We have talked about the problems o...

Lack of Redundancy We have talked about the problems of repetition of information in a database. Such repetition should be stay away as much as possible. Let us state once again t

Data warehouse, 1) Define a job scheduling strategy that will meet business...

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

Example database application, We will explain here an example database appl...

We will explain here an example database application having COLLEGE database and use it in showing several E-R modelling concepts. College database remains track of faculty, Stu

Managing Data in Databases, Answer SQL Queries to extract data from data ta...

Answer SQL Queries to extract data from data tables and questions on mapping conceptual data models into relational data model.

Data aggregation, Q.   Explain  data aggregatio n and discuss differen...

Q.   Explain  data aggregatio n and discuss different design constraints. Sol. Aggregation   One limitation of the E-R model is that it cannot express relationships amon

Define normalization, Normalization :It is a process of examine the given ...

Normalization :It is a process of examine the given relation schemas based on their primary key and Functional Dependencies (FDs) to achieve the properties Minimizing redun

What are the desirable properties of a decomposition, Define What are the d...

Define What are the desirable properties of a decomposition Ans: What are the desirable properties of decomposition - dependency preserving.  Because Lossless join and dependen

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