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 instance and schema, Define instance and schema?  Instance:  C...

Define instance and schema?  Instance:  Collection of  data  kept in the  data  base  at  a  particular  moment  is  known as an Instance of the database.  Schema: The o

Explain the exec statement in sql, Explain the Exec statement in SQL An...

Explain the Exec statement in SQL Ans: Exec statement has the structure    EXEC SQL END-EXEC   Embeded SQl statements are of a form identical to non embedded SQL statem

Query evolution, what is query processing ,query optimization and performan...

what is query processing ,query optimization and performance turring?

Dataware house, ) Define a job scheduling strategy that will meet business ...

) 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 picto

Define the relations as tables in sql, Consider the relations given below ...

Consider the relations given below Borrower (id_no, name) Book (accno., title, author, borrower_idno) (a) Define the above relations as tables in SQL forming real world assumptio

Need vmware technical support, Project Description: Critical Project for...

Project Description: Critical Project for VMware Technical support. VMWare ESXi 5.1 support for upgradation and migration problem. Technical expert of Vmware needed. Sk

Which model is used to store data in tree structures, 1. Which model is use...

1. Which model is used to store data in tree structures Ans: Hierarchical model is used to store data in tree structures

How to insert data in your table from another table, How to Insert data in ...

How to Insert data in your table from another table? insert into e.g, To insert tuples from employee into N_emp created above, use following statement Insert into N_emp

Define deadlock prevention, Define Deadlock prevention These protocols...

Define Deadlock prevention These protocols make sure that the system will never enter a deadlock state. There are two methods to deadlock prevention. One approach makes sure t

How can we classify the operations on classes, How can we Classify the oper...

How can we Classify the operations on classes  This step fundamentally means all three models functional, object and dynamic (studied in last section) must be combined so that

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