Dr Gordon Russell, Napier University M/C Walkthrough - V2.0 1 Multi-Choice Walkthrough

Dr Gordon Russell, Napier University M/C Walkthrough - V2.02 Q1 A publishing company produces academic books on various subjects. Books are written by authors who specialise in one or more particular subject. The company employs a number of editors who do not have particular specialisations but who take sole responsibilty for for editing one or more publications. A publication covers a single subject area but may be written by one or more author - the contribution of each author is recorded as a percentage for the purposes of calculating royalties. A publishing company produces academic books on various subjects. Books are written by authors who specialise in one or more particular subject. The company employs a number of editors who do not have particular specialisations but who take sole responsibilty for for editing one or more publications. A publication covers a single subject area but may be written by one or more author - the contribution of each author is recorded as a percentage for the purposes of calculating royalties.

Dr Gordon Russell, Napier University M/C Walkthrough - V2.03 Q1 Continued The following ER diagram is intended to represent the above specification: The following ER diagram is intended to represent the above specification:

Dr Gordon Russell, Napier University M/C Walkthrough - V2.04 Q1 Options Indicate the relation which has an incorrect cardinality shown: A. specialises in A. specialises in B. makes B. makes C. is about C. is about D. to D. to E. None of the above E. None of the above

Dr Gordon Russell, Napier University M/C Walkthrough - V2.05 Q2 The specification is to be changed so that an author can develop a publication covering more than one subject area and that the schema must be able to store the percentage of the compents concerned with each of the subjects. Select an appropriate change to the ER diagram: The specification is to be changed so that an author can develop a publication covering more than one subject area and that the schema must be able to store the percentage of the compents concerned with each of the subjects. Select an appropriate change to the ER diagram: A. publication-subject becomes many to many A. publication-subject becomes many to many B. author-subject becomes many to many B. author-subject becomes many to many C. author-publication becomes many to many C. author-publication becomes many to many D. more than one of the above D. more than one of the above E. none of the above E. none of the above

Dr Gordon Russell, Napier University M/C Walkthrough - V2.06 Q3 Consider the relational schema R(A,B,C,D,E) with non-key functional dependencies C,D - E and B - C. Consider the relational schema R(A,B,C,D,E) with non-key functional dependencies C,D - E and B - C. Select the strongest statement that can be made about the schema R Select the strongest statement that can be made about the schema R A. R is in first normal form A. R is in first normal form B. R is in second normal form B. R is in second normal form C. R is in third normal form C. R is in third normal form D. R is in BCNF normal form D. R is in BCNF normal form E. None of the above E. None of the above

Dr Gordon Russell, Napier University M/C Walkthrough - V2.07 Q4 Locking was introduced into databases so that Locking was introduced into databases so that A. Keys can be provided to maintain security. A. Keys can be provided to maintain security. B. Reading and writing is possible. B. Reading and writing is possible. C. All simultaneous transactions are prevented. C. All simultaneous transactions are prevented. D. Passwords can be provided to maintain security D. Passwords can be provided to maintain security E. Consistency can be enforced. E. Consistency can be enforced.

Dr Gordon Russell, Napier University M/C Walkthrough - V2.08 Q5 When accessing a disk block, the seek time When accessing a disk block, the seek time A. is insignificant in comparison to transfer times A. is insignificant in comparison to transfer times B. is about the same as transfer times B. is about the same as transfer times C. greatly exceeds transfer times C. greatly exceeds transfer times D. is the time taken to search for data in a sorted list of database rows D. is the time taken to search for data in a sorted list of database rows E. is measured in nanoseconds E. is measured in nanoseconds

Dr Gordon Russell, Napier University M/C Walkthrough - V2.09 Q6 Hash-table insertions Hash-table insertions A. avoid hash-collisions by manipulating the foreign keys A. avoid hash-collisions by manipulating the foreign keys B. might use hash-chains to allow hash-collisions B. might use hash-chains to allow hash-collisions C. use balanced binary trees to allow hash-collisions C. use balanced binary trees to allow hash-collisions D. use primary keys to avoid hash-collisions D. use primary keys to avoid hash-collisions E. become unusable if there are any hash-collisions E. become unusable if there are any hash-collisions

Dr Gordon Russell, Napier University M/C Walkthrough - V2.010 Q7 When a transaction aborts When a transaction aborts A. all users must be notified A. all users must be notified B. all changes it has made are immediately available to other transactions B. all changes it has made are immediately available to other transactions C. the modifications of all transactions currently running are also aborted C. the modifications of all transactions currently running are also aborted D. it can abort transactions which have already committed D. it can abort transactions which have already committed E. it releases all of its locks E. it releases all of its locks