Suppose we map this to the relational model as follows:

PERSON (

COMPANY (

ACCOUNT-HOLDER (CustNo, ...)

Which statement is correct? The categorisation can also be modelled as a specialisation. incorrect We cannot guarantee that the tuples of the category relation are a subset of the union of the tuples of the superclasses. correct The foreign keys P-CustNo and C-CustNo should be defined as NOT NULL. incorrect The categorisation can be perfectly mapped to the relational model. incorrect MC Given the following relations:

Book (

Library is a foreign key referring to 'zip code' in 'Library'. This value can be NULL.

Library (

Customer (

Loan (

ISBN is a foreign key referring to 'ISBN' in 'Book' and cannot be NULL.

customerID is a foreign key referring to 'ID' in 'Customer' and cannot be NULL.

Which statement is not correct? All the relations are in 2NF but not in 3NF. correct A customer can loan multiple books. incorrect A library can be uniquely identified based on its zip code. incorrect A book can be loaned by different customers. incorrect MC Consider following generalization / specialization.

Suppose we represent this generalization / specialization by the following relational model:

Discipline (

Individual sport (

Teamsport (

Consider the following 4 statements:

1) The relational model does not allow to enforce the completeness constraint; the disjointness constraint can be enforced.

2) The relational model does not allow to enforce both the completeness constraint and the disjointness constraint.

3) By dropping the relation 'Discipline' in the relational model, the completeness constraint can be enforced.

4) The relational model allows the specialization to be partial.

Which of the following options is CORRECT? Only statement 4 is incorrect, the other statements are correct. incorrect Statement 1 and 4 are both incorrect. incorrect Statement 1 and 2 are both correct. incorrect Only statement 1 is incorrect, the other statements are correct. correct MC

Which of the following statements on mapping the above EER model to a relational model is correct? We cannot enforce all four cardinalities of the EER relationship type between 'Bungalow' and 'Reservation'. correct The minimum cardinality of 1 at the side of 'Customers' in the EER relationship type between 'Customers' and 'Ticket' cannot be enforced. incorrect We cannot enforce that the EER specialization is total in the relational model. incorrect We cannot enforce all four cardinalities of the EER relationship type between 'Park' and 'Activity area'. incorrect MC Given the following relation:

HospitalRoom (

Which statement is not correct? 'city' is transitive dependent on the primary key. incorrect '(hospitalID, roomNR)' is a minimal superkey. incorrect 'roomNR' is a prime attribute type. incorrect Every non-prime attribute of this relation is fully functionally dependent on any key of this relation. correct MC Consider the following ER model for a course administration.

Which statement is NOT CORRECT? When mapping the ER relationship type organizes between Course and Session to the relational model, the primary key "cnb" of the Course relation will be included as a NOT NULL foreign key in the Session relation. The 4 cardinalities of this ER relationship type can be perfectly mapped to the relational model. incorrect When mapping the ER relationship type teaches between Session and Teacher to the relational model, a new relation needs to be introduced. The 4 cardinalities of this ER relationship type can be perfectly mapped to the relational model. correct When mapping the ER relationship type enrollment between Session and Student to the relational model, a new relation needs to be introduced. The 4 cardinalities of this ER relationship type can be perfectly mapped to the relational model. incorrect Both the ER and the relational model cannot enforce that a teacher can only teach sessions of courses for which he/she is qualified. incorrect MC

In order to turn this EER model into a fully normalised relational model, how many relations do we need? 8 incorrect 6 correct 5 incorrect 7 incorrect MC

Which statement is NOT CORRECT when mapping the above EER model to a relational model? The minimum cardinality of 1 at the side of 'Restaurant' in the EER relationship type between 'Restaurant' and 'Table' can be successfully mapped to the relational model. incorrect We should create a new relation to model the EER relationship type between 'Table' and 'Reservation'. incorrect To map the weak entity type 'Table' to a relation, we should add the foreign key 'restaurant name' to the corresponding relation and ensure that is not NULL. incorrect The minimum cardinality of 1 at the 'Table' side of the EER relationship type between 'Table' and 'Reservation can be successfully mapped to the relational model. correct MC Given the following (normalized) relational model (primary keys underlined; foreign keys in italics):

EMPLOYEE(

SUPERVISOR:

DNR:

DEPARTMENT(

MGNR:

PROJECT(

DNR:

WORKS_ON(

SSN:

PNR:

Which statement is NOT CORRECT? Every project is always assigned to exactly one department. incorrect A department has always exactly one manager. incorrect According to the model, an employee can work in another department than he/she manages. incorrect Every employee must be always supervised by exactly one other employee. correct MC Which statement is CORRECT? In mapping an EER N:M relationship type to the relational model, we create a new relation R. Its primary key is the combination of the foreign keys referring to the primary keys of the relations corresponding to the participating entity types. correct A minimum cardinality of 1 in the EER model can never be enforced in the relational model. incorrect An EER relationship type always asks for the creation of a new corresponding relation R in the relational model. incorrect An EER aggregation cannot be mapped in a straightforward way to a relational model. incorrect