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

Update operations, The Update Operations : Update operations are used fo...

The Update Operations : Update operations are used for altering database values. The constraint violations faced by this operation are logically the similar as the problem faced

Define an operator that a relational algebra does not have, Define an opera...

Define an operator that a Relational Algebra does not have Ans: Relational Algebra does not have Aggregation operators.

Differentiate between a global and a local temporary table, Differentiate b...

Differentiate between a Global and a Local temporary table? - A local temporary table exists only for the duration of a connection or if defined inside a compound statement, fo

Normalization, in case of functional dependencies how we get the higher nor...

in case of functional dependencies how we get the higher normal form.

What is storage manager, What is storage manager?  A  storage  manager ...

What is storage manager?  A  storage  manager  is  a  program  module  that  gives  the  interface  between the Low level data  kept in a database and the application programs

Define query processing, Define Query Processing Query processing is th...

Define Query Processing Query processing is the process of selecting the best plan or strategy to be employed in responding to a database request. The plan is then executed to

Advantages to copying records from one table to another, What kind of advan...

What kind of advantages to copying records from one table to another? -) When an algorithm that modifies a table is used after that it's safer to work with the copy -) When

Write short notes on relational model, Write short notes on relational mode...

Write short notes on relational model The relational model uses a collection of tables to show both data and the relationships between those data. The relational model is an ex

Why a report generator is used, Why a report generator is used ? Report...

Why a report generator is used ? Report generator is used for print files on paper.

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