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."
Critically evaluate the bulleted list of information-related items in this case study. How are each contradictory to the notion of being an information-literate knowledge worker?
Explain the differences between structured data and unstructured data. Structured data are facts concerning objects and events. The most significant structured data are numeric
Ask questioYou are the database administrator in a university. You have been tasked to come up with a new database for the University. Using the stages in Database Life Cycle come
What are the disadvantages of relational approach? Disadvantages of relational approach: • Substantial hardware and system software overhead • May not fit all business models •
Determine the Advanced modeling concepts You have to follow some steps for object-oriented design. These steps for OO Design methodology are as follow: 1) Produce objec
Can you assist me in Database management system? I need help in my courses, please email me at and get back me soon...
CAN SOMEONE HELP ME WITH ENTITY DIAGRAMS IN FIRST NORMAL FORM?
Attributes and its types explain?
What is a primary index? A primary index is an index whose search key also explains the sequential order of the file.
what is un ordered and ordered file managment?
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