What is completeness constraint on generalization, Database Management System

Assignment Help:

What is completeness constraint on generalization? Define the variation between total and partial design constraint. Give an example each.    

 Ans: Completeness Constraints 

1. Total specialization  constraint

a. Each entity in the superclass should be a member of some subclass in the specialization for example {HOURLY_EMPLOYEE, SALARIED_EMPLOYEE} 

b. Notation: superclass 

2. Partial specialization constraint an entity might not belong to any type of the subclasses 

For example: {SECRETARY, ENGINEER, TECHNICIAN}


Related Discussions:- What is completeness constraint on generalization

Define transitive dependencies, What do you understand by transitive depend...

What do you understand by transitive dependencies? Define with an example any two problems that can take place in the database if transitive dependencies are available in the datab

Explain the exec statement in sql, Explain the EXEC statement in SQL  A...

Explain the EXEC statement in SQL  Ans: All statements which start with EXEC SQL are embedded SQL database statements. High level languages such as C can be employed to write a

Frequecy count, how to calculate frequency count of algorithm

how to calculate frequency count of algorithm

Checkpoint, what is check point in database management system

what is check point in database management system

Name the various privileges in sql, Name the various privileges in SQL? ...

Name the various privileges in SQL? A) Delete B) Select C) Insert D) Update

DSS, WHAT IS DSS? WRITE ITS REQUIREMENTS.

WHAT IS DSS? WRITE ITS REQUIREMENTS.

What is the aim of logical schema, What is the aim of logical schema ? ...

What is the aim of logical schema ? The main motive of the logical schema is to ensure the portability of procedures and models on various physical schemas at runtime.

Related fields in a database are grouped in which form, Related fields in a...

Related fields in a database are grouped in which form? Related data fields in a database are grouped to form a data record. (A record is a collection of related fields)

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

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