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!
FDs in Relationships:
Enrols Relationship: None as it is many to many
Teaches Relationship: Course code → Instructor
Instructor → Course code
The next question is: How do we recognize the functional dependence in a database model?
Functional dependencies occur from the nature of the actual world that the database models. Often A and B are facts about an entity where A may be some identifier for the entity and B some characteristic. Functional dependencies cannot be automatically determined by studying one or more cases of a database. They can be determined only by a careful study of the actual world and a clear understanding of what every attribute means.
There are no thumb rules for determining FDs.
Functional dependence is an vital concept and a large body of formal theory has been developed about it.
explaination
What do you mean by DBMS? What is its need and what are its goals. Explain? OR Explain Data Base Management System? Sol. Database management system is a
One-to-many : An entity in A is related with any number of entities in B. An entity in B is related with at the most one entity in A. Example: Relationship between faculty and d
Association as a cache This association must be updated when any new element is added to it, but testing for overlap using association is more efficient. Figure:
Creating views with Read only option : In the view definition this option is used to make sure that no DML operations can be done on the view.
Compute the closure (F+) for the following set of the functional dependencies defined on R(a,b,c,d), where F - {c→ a, ab → d, a → b, d → c}, i.e. what are all of the FDs implied b
What is substitutability? Any method of a class-say A can equally well be adjured with any object belonging to any subclasses B of A. This characteristic leads to code reuse, a
(a) Provide the description of the following ODMG schema in the Object Definition Language (ODL). (b) Based on the above object database, write the following queries i
The Third Normal Form (3NF) Even though, transforming a relation that is not in 2NF into a number of relations that are in 2NF take out many of the anomalies, it does not neces
NEED FOR A DATABASE MANAGEMENT SYSTEM A Database is a structured, persistent collection of data of an organisation. The database management system (DBMS) manages the database o
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