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!
Dependency Preservation
It is obvious that the decomposition must be lossless so that we do not lose any information from the relation that is decomposed. Dependency preservation is another main requirement since a dependency is a constraint on the database. If each attributes appearing on the left and the right side of a dependency appear in the similar relation, then a dependency is considered to be preserved. Therefore, dependency preservation can be checked simply. Dependency preservation is important, because as stated previously, dependency is a constraint on a relation. Therefore, if a constraint is split over more than one relation (dependency is not preserved), the constraint would be complex to meet. We will not talk about this in more detail in this unit. You may refer to the more readings for more details. Though, let us state one basic point:
"A decomposition into 3NF is lossless and dependency preserving whereas a decomposition into BCNF is lossless but may or may not be dependency preserving."
Describe Hashing in DBMS? Hashing: Hashing is a technique to store data within an array so which storing, searching, inserting and deleting data is fast (in theory it's O(1))
Illustrate the Deployment Diagram A deployment diagram shows all nodes on network, their processor execution and interconnections. In a dynamic model, this is used to represen
Define Database layer? The database layer defines the data formats used in the database.
Example -Find the employee name, salary, department number and average salary of his/her department, for those employees whose salary is more than the average salary of that depart
Every School has many teachers and many students. Each student is assigned to one school and each teacher works for one school only. Each teacher teaches more than one subject but
Process of normalization is the integral part of designing a database. Justify this statement with suitable database design
object oriented database
Project: Microsoft Access You have been asked by the ABC Tanning Salon to create a database that can be used to track the salon's customers. You are to create a table in Access
Defining Internal Classes and Operations When we enlarge algorithms, new classes can be added to the store intermediate results. A complex operation could be looked at, as a c
i want to database for online assignment submission system
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