Define cardinality and participation constraints, Database Management System

Assignment Help:

Define cardinality and participation constraints on a relationship type, completeness constraint on generalization.       

Ans: Cardinality defines the number of entities to which other entity can be related via a relationship set. It may be 1:1, 1: N or M: N.

 In a relationship set Participation of an entity set can be total or partial. It is total if each entity participates in the relationship. If only a few entities participate in a relationship after that it is partial.

Completeness constraint may be partial or total. In the case of total every higher level entity must belong to a lower level entity and in the case of partial few higher level entities might not belong to lower level entities.


Related Discussions:- Define cardinality and participation constraints

Database design in third normal form, The following data are required to be...

The following data are required to be stored by a family physician. Family#, FamilyAddress, Patient#, PatientName, ServiceCode, ServiceFee, ServiceDate A family can have seve

Adding redundant associations for efficient access, Adding Redundant Associ...

Adding Redundant Associations for Efficient Access Redundant associations do not add any type of information, therefore during design we should actually examine structure of o

Spanned and unspanned organisation, Spanned and unspanned organisation? ...

Spanned and unspanned organisation? Spanned and unspanned organization: If records are not permited to cross block boundaries then the organisation is called unspanned record

State about the tables- DBMS, State about the Tables- DBMS Data is sto...

State about the Tables- DBMS Data is stored in columns and rows (much like a spreadsheet -main difference is how data is organised). Every row in a table is known as a record

Wait-die scheme -deadlock prevention, Wait-die" scheme : The idea is based ...

Wait-die" scheme : The idea is based on non-preventive method. It is based on a simple rule:                                 If Ti requests a database resource that is held by T

Information infrasture, what benefit can a company gain by managing its own...

what benefit can a company gain by managing its own infrasture and services

Describe file organisation, Describe file organisation? A file is organ...

Describe file organisation? A file is organized logically as a sequence of records. These records are mapped onto disk blocks. A) Fixed-Length Records Type deposit=record

Define shadow paging, Define shadow paging. An alternative to log-based...

Define shadow paging. An alternative to log-based crash recovery method is shadow paging. This technique requires fewer disk accesses than do the log-based methods.

What is a project operation, What is a PROJECT operation? The project o...

What is a PROJECT operation? The project operation is a unary operation that returns its argument relation with particular attributes left out. Projection is shown by pie (π).

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