MC	Which statement is NOT CORRECT?	A relation is in 3NF if it is in 2NF and no non-prime attribute type of R is transitively dependent on the primary key	incorrect	A foreign key can be NULL.	incorrect	A relation cannot have more than 1 foreign key.	correct	A prime attribute type is an attribute type that is part of a candidate key. 	incorrect	
MC	Consider a data model for the Olympics storing information about countries and athletes.  There is a 1-N relationship type between country and athlete and an athlete always has to belong to exactly 1 country.  A relational data model containing only 1 table leads to:	No unnecessary replication of data.	incorrect	Unnecessary replication of data about athletes and countries.	incorrect	Unnecessary replication of data about countries.	correct	Unnecessary replication of data about athletes.	incorrect	
MC	Given the following relational model (primary keys are underlined, foreign keys are in italics)<br><br>BOOK(<u>ISBN</u>, title, pages, price, <em>publishername</em>)<br>AUTHOR(<u>authorname</u>, date_of_birth)<br>WRITES(<u><em>authorname</em></u>, <u><em>ISBN</em></u>)<br>PUBLISHER(<u>publishername</u>, streetnumber, streetname, <em>zipcode</em>)<br>CITY(<u>zipcode</u>, city)<br><br>The assumptions are: <ul><li>Each book has a unique ISBN number</li><li>Each author has a unique name</li><li>Each publisher has a unique name</li><li>A book can have multiple authors</li><li>An auther can write more than one book</li><li>A publisher can publish more than one book</li><li>A book can have multiple publishers</li><li>A publisher has only one address</li></ul>Which statement is CORRECT?	The relational model is in third normal form.	incorrect	The relational model is not in first normal form.	correct	The relational model is in second normal form but not in third normal form.	incorrect	The relational model is in first normal form but not in second normal form.	incorrect	
MC	Consider the following EER model <br><br><img class="img-fluid" src="http://www.pdbmbook.com/static/quiz/fig6_10.png"><br><br>Which statement is CORRECT?	When mapping the EER relationship type INVOLVE between COURSE and ASSIGNMENT to the relational model, a new relation needs to be introduced. The 1..1 cardinalities of this relationship type cannot be enforced in the relational model.	incorrect	When mapping the EER relationship type IS_ENROLLED between COURSE and STUDENT to the relational model, a new relation needs to be introduced. The relation is identified by GRADE as its primary key.	incorrect	When mapping the EER relationship type PARTICIPATE between GROUP ASSIGNMENT and STUDENT to the relational model, a new relation needs to be introduced. The 4 cardinalities of this EER relationship type can be perfectly mapped to the relational model.	incorrect	The partial inheritance relationship between STUDENT and REPRESENTATIVE can be perfectly mapped to the relational model by the following two relations: STUDENT(StudentID, FirstName, LastName) and REPRESENTATIVE (S-StudentID, Email) whereby S-StudentID refers to StudentID in STUDENT.  	correct	
MC	Which statement is NOT CORRECT?	The Boyce Codd normal form is more strict than the third normal form.	incorrect	Every relation must have a foreign key.  	correct	A relation is in 3NF if it is in 2NF and no non-prime attribute type of R is transitively dependent on the primary key	incorrect	A prime attribute type is an attribute type that is part of a candidate key. 	incorrect	
MC	Which statement is CORRECT?	A foreign key of a relation A cannot refer to the primary key of the same relation A.	incorrect	A relation cannot have more than 1 foreign key.	incorrect	A foreign key can be NULL.	correct	Every relation must have a foreign key.  	incorrect	
MC	Given the following (normalized) relational model (primary keys underlined; foreign keys in italics):<br><br>EMPLOYEE(<u>SSN</u>, ENAME, EADDRESS, SEX, DATE_OF_BIRTH, <em>SUPERVISOR</em>, <em>DNR</em>)<br>SUPERVISOR: <em>foreign key, refers to</em> SSN in EMPLOYEE, <em>NULL value not allowed</em><br>DNR: <em>foreign key, refers to</em> DNR in DEPARTMENT, <em>NULL value not allowed</em><br><br>DEPARTMENT(<u>DNR</u>, DNAME, DLOCATION, <em>MGNR</em>)<br>MGNR: <em>foreign key, refers to</em> SSN in EMPLOYEE, <em>NULL value not allowed</em><br><br>PROJECT(<u>PNR</u>, PNAME, PDURATION, <em>DNR</em>)<br>DNR: <em>foreign key, refers to</em> DNR in DEPARTMENT, <em>NULL value not allowed</em><br><br>WORKS_ON(<u><em>SSN, PNR,</em></u> HOURS)<br>SSN: <em>foreign key, refers to</em> SSN in EMPLOYEE, <em>NULL value not allowed</em><br>PNR: <em>foreign key, refers to</em> PNR in PROJECT, <em>NULL value not allowed</em><br><br>Which statement is NOT CORRECT?	A department has always exactly one manager.	incorrect	Every employee must be always supervised by exactly one other employee.	incorrect	Every project is always assigned to exactly one department.	incorrect	An employee must work in the same department than he/she manages.	correct	
MC	The following relational model represents a HRM system of a consultancy firm. The primary keys are underlined while foreign keys are in italic font.<br><br>Consultant (<u>ConsultantID</u>, Date of Birth, Expertise)<br><br>Assigned_to (<u><em>ConsultantID</em>, <em>ProjectID</em></u>)<br><em>ConsultantID</em> refers to ConsultantID in Consultant<br><em>ProjectID</em> refers to ProjectID in Project<br><br>Project (<u>ProjectID</u>, Description, Type, <em>Company</em>)<br><em>Company</em> refers to Name in Company<br><br>Company (<u>Name</u>, Location)<br><br>Suppose a new consultant is hired and immediately assigned to a new training project at a new firm and to 2 other, already existing projects. How many rows (tuples) must be added to the database to reflect this change? 	6	correct	1	incorrect	5	incorrect	3	incorrect	
MC	The following relational model represents a HRM system of a consultancy firm. The primary keys are underlined while foreign keys are in italic font.<br><br>Consultant (<u>ConsultantID</u>, Date of Birth, Expertise)<br><br>Assigned_to (<u><em>ConsultantID</em>, <em>ProjectID</em></u>)<br><em>ConsultantID</em> refers to ConsultantID in Consultant<br><em>ProjectID</em> refers to ProjectID in Project<br><br>Project (<u>ProjectID</u>, Description, Type, <em>Company</em>)<br><em>Company</em> refers to Name in Company<br><br>Company (<u>Name</u>, Location)<br><br>Suppose a new consultant is hired and immediately assigned to a new training project at a new firm and to 2 other, already existing projects. How many rows (tuples) must be added to the database to reflect this change? 	5	incorrect	6	correct	1	incorrect	3	incorrect	
MC	Consider following generalization / specialization.<br><br><img class="img-fluid" src="http://www.pdbmbook.com/static/quiz/fig6_9.png"><br><br>Suppose we represent this generalization / specialization by the following relational model:<br><br>Discipline (<u>Disciplinenr</u>, Name)<br>Individual sport (<u><em>Disciplinenr</u></em>) <em>Disciplinenr</em> refers to Disciplinenr in Discipline<br>Teamsport (<u><em>Disciplinenr</u></em>, Number players) <em>Disciplinenr</em> refers to Disciplinenr in Discipline<br><br>Consider the following 4 statements:<br>1) The relational model does not allow to enforce the completeness constraint; the disjointness constraint can be enforced.<br>2) The relational model does not allow to enforce both the completeness constraint and the disjointness constraint.<br>3) By dropping the relation 'Discipline' in the relational model, the completeness constraint can be enforced.<br>4) The relational model allows the specialization to be partial.<br><br>Which of the following options is CORRECT?	Statement 1 and 4 are both incorrect.	incorrect	Statement 1 and 2 are both correct.	incorrect	Only statement 4 is incorrect, the other statements are correct.	incorrect	Only statement 1 is incorrect, the other statements are correct.	correct