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

Finkelstein methodology, PART MARKING: For this section, we will use part m...

PART MARKING: For this section, we will use part marking. This means we will supply model answers to all questions but we will only mark six questions. We will choose these randoml

Perform an exploratory analysis on the entire dataset, Australian Bureau of...

Australian Bureau of Statistics (ABS) provides retail data for different groups and different states as well as the aggregate numbers. Table 11 " Retail Turnover, State by Industry

Creation of indexes, Creation of Indexes Automatically: When a primar...

Creation of Indexes Automatically: When a primary key or Unique constraint is show in a table definition then a unique index is formed automatically. Manually: User can

Explain the natural join, Explain the Natural join Natural join is a bi...

Explain the Natural join Natural join is a binary operator which is written as (R* S) in which R and S are relations. The effect of the natural join is the set of all combinati

Introduction to database technology, 1. Create the tables for the play-sche...

1. Create the tables for the play-scheme database as specified in the TMA. 2. Enter the data as given in the spreadsheet. 3. Create queries to retrieve specified information

What is null, What is NULL? Simply NULL means not in value.

What is NULL? Simply NULL means not in value.

Issues relating to the design of the physical database files, The issues re...

The issues relating to the Design of the Physical Database Files Physical File is a file as stored on the disk. The major issues relating to physical files are:  •      Cons

What is the highest normal form of the table - normalization, In problems 1...

In problems 1 - 4, you are given the columns of a table, and a set of functional dependencies.  Determine the normal form of this table.  Remember that the normal form is the HIGHE

design the logic using looping structure, 1. Design the logic, using a loo...

1. Design the logic, using a looping structure, for a program that outputs every even number from 1 through 25 along with its square and cube. 2. Mr. Sanchez owns 12 apartme

What are the categories of sql command, What are the categories of SQL comm...

What are the categories of SQL command? SQL commands are separated in to the following categories: 1. Data - Definitition Language 2. Data Manipulation language 3. Dat

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