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."
Which data type can store unstructured data? Raw data type can store unstructured data.
Importance Of File Organisation In Database To execute a database efficiently, there are various design tradeoffs needed. One of the most vital ones is the file Organisation. F
Question 1: a) What is the difference between a non-impact and impact printer? b) Which type of printer is generally used in a supermarket to print your receipt? Describe
Consider entity type Employee with attributes empNumber (this is unique), empName, and the year when he/she was hired. An employee can either be a technical employee, a marketing e
1. Use the Invoice table structure shown below to answer the following questions: a) Draw the dependency diagram and identify the primary key and all dependencies, including al
QUESTION (a) Give two advantages of using Linked List as compared to arrays. (b) (i) You are working as programmer at the Orange Mauritius branch. You have been asked to cre
Report writing help on database mgmt Project Description: Use of Harvard referencing, critical analysis is required. Skills required: Academic Writing, Technical Writin
Explain the function of input controls. Identify four types of input control and explain the function of each. Provide an example of a data integrity error that could occur i
The users who use easy-to-use menu are called ? The users who use easy to use menu are called as Naïve users.
Describe how you can simplify Operations. To simplify operation, one should use inheritance, where possible to use, to reduce the quantity of distinct operations. Introduce new
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