Toggle navigation
Menu
Tutors
Study Help
Scholarships
Projects
Ask a Question
Sign In
Register
{{navbarsearch}}
in
Textbook Solution
Computer Sciences
Databases
Suppose there are two relations r and s such that
Suppose there are two relations r and s such that
Suppose there are two relations r and s, such that the foreign key B of r references the primary key A of s. Describe how the trigger mechanism can be used to implement the on delete cascade option, when a tuple is deleted from s.
Students also viewed these questions
Write an assertion for the bank database to ensure that the assets value for the Perryridge branch is equal to the sum of all the amounts lent by the Perryridge branch.
For each of the views that you defined in Exercise 6.10, explain how updates would be performed (if they should be allowed at all).
Suppose that we decompose the schema R = (A, B, C, D, E) into (A, B, C) (A, D, E). Show that this decomposition is a loss less-join decomposition if the following set F of functional dependencies holds: A → BC CD ...
Use Armstrong’s axioms to prove the soundness of the pseudotransitivity rule.
Show that it is possible to ensure that a dependency-preserving decomposition into 3NF is a loss less-join decomposition by guaranteeing that at least one schema contains a candidate key for the schema being decomposed.
Membership
TRY NOW
Access to
800,000+
Textbook Solutions
Ask any question from
24/7
available
Tutors
Live Video
Consultation with Tutors
50,000+
Answers by Tutors
OR
$ 1.99
VIEW SOLUTION
ADD TO CART
Relevant Tutors available to help
Christine Kanyaa
business management
Caroline Njeri
Business Administration
Keziah Thiga
Business Management
×
NO,THANKS
TRY NOW