Download Written part of the exam

Principles of database management
Exam questions (JANUARY 2016)
Written part of the exam
Question 1
Given the following EER model (a model presenting a company selling beers, with a partial
specialisation, and 0:N, 1:N or n:M relationships, no multivalued or composite attribute)
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Discuss some semantics that are not covered by the model, give examples.
Transform the EER model into a relational model. Clearly specify the primary and
foreign key and the not null constraints. Are there semantics are lost? Are there
semantics added? Which ones?
Question 2
Define briefly the following concepts
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view with check option
SQL query with NOT EXISTS (illustrate it with an example)
DML procedural language
3rn normal form (illustrate with an example)
Shared aggragation (illustrate with an example)
Oral exam – Prof. Baesens
A LOT of very small and fast questions about some details of the models.
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What is this? (Showing an weak entity in EER)
Is a weak entity type always existent dependent?
Is an existent dependent entity always an entity type?
What is this? (Showing a partial overlap specialisation in EER)?
If you wanted to represent this relationship (in the EER model) in a relational model,
how would you do that? (it was a 1:N relationship, he asked afterwards on which side
I should put the foreign key)
What is this (showing the p of the partial specialisation)?
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(In the Codasyl) why do you need the record type “registered_for”?
(In the Codasyl model), is this a specialisation? What semantics are lost here?
In the Codasyl model, there are record types and?
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In the relational model, can a foreign key be null? If yes, in which case?
What does this on delete cascade mean?
(In the relational model), is this a foreign key? Why do you need it? Is it not null?
Why?
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What does UML stands for?
What is this (showing a qualified aggregation in UML)?
Oral exam – Prof. Lemahieu
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Explain what is staging area. What are the differences and the similarities with an
operational data store (ODC)
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How would you modify this architecture for a web browser than cannot use applets?
You need to keep using the distributed objects.
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Context: a company that sells ice creams decide to implement a database. Through the
web, potential customers will be able to check and look for information about the ice
creams (flavours, stocks available, location of the stores, packaging,…). Moreover,
through an intranet, the employees of the company will be able to modify the data
about the ice screams (flavours, stocks, etc). In this context, how could the different
concepts be used? How would they be useful?
 Host language variables
 Rich internet applications
 Optimistic concurrency