Strong entity set and weak entity set, Database Management System

Assignment Help:

Strong entity set and weak entity set?

Strong entity set and weak entity set: A strong entity set has a primary key. All tuples in 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 involved. Tuples in a weak entity set are partitioned according to their relationship along with tuples within a strong entity set. Tuples within each partition are distinguishable through a discriminator that is a set of attributes. A strong entity set has a primary key. All tuples in 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 every partition are distinguishable through a discriminator, which is a set of attributes.


Related Discussions:- Strong entity set and weak entity set

Explain the timestamps for read operations, Timestamps For Read operations:...

Timestamps For Read operations: If TS (T) If TS (T) >= W-timestamp (Q), then the transaction T is trying to read a value of data item Q which has been written and committed

Explain mechanism of nested queries, Explain mechanism of nested queries? ...

Explain mechanism of nested queries? SQL gives a mechanism for nesting subqueries. A subquery is a select from where expression that is nested within one more query. A common u

What is indexed sequential file organization, What is indexed sequential fi...

What is indexed sequential file organization? What are the applications of this organization?  Ans: An index file can be employed to effectively overcome the problem of storing

What does conceptual design work, What does conceptual design work? A c...

What does conceptual design work? A conceptual design involves modelling independent of the DBMS.

Implementing a distributed database system, A distributed database is defin...

A distributed database is defined as "a collection of multiple logically interrelated database which are physically distributed over a computer network" (a) Give any three advan

North indian plains, i am not clear with the climetic condition of the nort...

i am not clear with the climetic condition of the north indian plain. can u plz explain it for me

How to create values of structured type, How to create values of structured...

How to create values of structured type? Constructor functions are used to make values of structured types. A function with the similar name as a structured type is a construct

Explain olap and the benefits of olap, Data Mining 1. What is data mini...

Data Mining 1. What is data mining? Write Data Mining applications. 2. Explain OLAP? Write the benefits of OLAP. 3. What are the key features of a Data Warehouse? 4. W

Provide the steps involved in ethical analysis, Question : Mr. Smith Ha...

Question : Mr. Smith Harry has a car manufacturing company which has recently integrated management information system. He wishes to obtain more information on ethics and socia

Explain the deferred update, Explain the Deferred Update The deferred ...

Explain the Deferred Update The deferred update methods do not physically update the database on disk till after a transaction reaches its commit point; after that the updates

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