Revision

Revision Questions

Note: these questions intend to test basic knowledge of some of the main concepts. These are not typical exam questions.

1. What is the relationship between

Redundancy
Inconsistency
Integrity

___________ can cause _______________
___________ avoids ______________

2. For each concept in the left column, find the terms in the right column that relate to it:

A) ANSI/SPARC model 1) fan, chasm

B) ER model 2) one-to-one, many-to-many, one-to-many

C) enhanced ER model (EER model) 3) external, conceptual, internal

D) cardinality 4) SELECT, INSERT, DELETE, CREATE, UPDATE

E) connection trap 5) entity, referential

F) integrity 6) traditional, modern, outer

G) aggregate functions 7) specialisation, generalisation

H) JOIN 8) max, sum, average

I) SQL 9) entity, attribute, relationship

3. For each description find the picture that belongs to it.

lost update scenario
uncommitted dependency scenario
inconsistency scenario
deadlock

4. Which of the scenarios below (A or B) is an immediate update and which is a deferred update?

A) ANSI/SPARC model	1) fan, chasm
B) ER model	2) one-to-one, many-to-many, one-to-many
C) enhanced ER model (EER model)	3) external, conceptual, internal
D) cardinality	4) SELECT, INSERT, DELETE, CREATE, UPDATE
E) connection trap	5) entity, referential
F) integrity	6) traditional, modern, outer
G) aggregate functions	7) specialisation, generalisation
H) JOIN	8) max, sum, average
I) SQL	9) entity, attribute, relationship