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!
Question:
This Question refers to the database schema given in the Appendix.
(a) The integrity of a database is enforced by integrity rules. Discuss what should happen on an attempt to delete the target of a foreign key reference (for example, to delete a lecturer in the LECTURER table who lectures at least one unit listed in the TIMETABLE table)? Your discussion should describe the three possible techniques which can be used to deal with the problem, and provide one example for each technique by using the above tables.
(b) Using the database schema, express the following queries in SQL:
(i) Create the TIMETABLE table including the primary and foreign key constraints in the code. Make any assumption you want to make.
(ii) Insert the first row in the TIMETABLE table and make any assumption.
(iii) Modify the code value to Workshop for the above record created assuming that the rest of the values have already been created.
(iv) Find the numbers of students who have achieved one or more final grade greater than 14.
(v) Find the student number, unit number and final grade for those students attending units run by the departments named ‘computing' or ‘accountancy'.
Set Difference If R1 and R2 are two union compatible relations or relations then result of R3 =R1- R2 is the relation that have only those tuples that are in R1 but not in R2.
What is meant by Physical blocks? The input and output operations are completed in block units. The blocks residing on the disk are referred to as physical blocks.
Define weak and strong entity sets? Weak entity set: entity set that do not have key attribute of their own are known as weak entity sets. Strong entity set
Use the IRIS dataset that comes with Weka to compare the classification performance of the following algorithms. 1. NaiveBayesSimple 2. MultiLayerPerceptron J48 (
The need for three level architecture The aim of the three level architecture is to divide each user's view of the database from the way the database is physically shown.
Attributes and its types explain?
Why is database redesign necessary? Database redesign is essential for two reasons. First, redesign is essential both to fix mistakes made during the initial database design. S
The domain that you will model in this assignment is that of courses and students at a university. So as not to make the task too large and unspecified, you will here get a descrip
Complexity : A distributed DBMS that is available, reliable, and secure is inherently more difficult than a centralised DBMS. Though, adequate data replication is essential to have
design a generalization specialization hierarchy for a motor vehicle sales company. the company sells motorcycles, passenger cars, vens and buses.
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