Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Relations create the database. They must satisfy various properties, like no duplicate tuples, no ordering of tuples, and atomic attributes, etc. Relations that satisfy these basic needs may still have some undesirable characteristics such as data redundancy, and anomalies.
What are these undesirable characteristics and how can we eliminate them from the database system? This part is an attempt to answer this question. Though, please note that most of these undesirable properties do not arise if the database modelling has been carried out very carefully using some method like the Entity-Relationship Model. It is still important to use the methods in this unit to check the database that has been acquired and ensure that no mistakes have been made in modeling.
The central thought in these discussions is the concept of Database integrity, the notion of functional dependency, which rely on understanding the semantics of the data and which deals with what information in a relation is dependent on what other information in the relation. Our prime objective in this section is to describe the concept of data integrity, functional dependence and then describes normal forms using functional dependencies and using other types of data dependencies.
OBJECTIVES
After reading this section you should be able to
You are to write a property management database program that allows a real estate agent to view, add, search, and save property listings. The program is to do the following: 1.
Distributed And Client Server Databases Introduction This unit tells the distributed database systems which are primarily relational and one important execution model: the
Consider the join of a relation R with relation S. If R has m tuples and S has n tuples, then the maximum size of join is: If R has m tuples and S has n tuples then maximum siz
Explain the term- Query. Queries are used to repossess and show specific records in a table. They can also be used to show specific fields of specific records, which meet the co
State as Location within a Program In this traditional approach, location of control inside a program totally defines the program state. Any finite state machine may be implem
A collection of a same kind of entities is known as an Entity Set or entity type. Example: For the COLLEGE database defines earlier objects of concern are Students, Faculty,
The participation Constraints shows whether the existence of an entity depends on its being associated to another entity by the relationship type. There are two kinds of participat
The Transactions- A transaction is definite as the unit of work in a database system. Database systems that deal with a huge number of transactions are also termed as transaction p
One-way Associations When an association is traversed only in the one direction, then it is implemented as a pointer i.e.an attribute which contains an object reference. If mu
Where does view definition stored? A view definition is permanently stored as part of the database.
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd