Questions and answers for exam Preparation

MCQs

Total Questions : 11 | Page 1 of 2 pages

Question 1. The situation where the lock waits only for a specified amount of time for another lock to be released is

Lock timeout
Wait-wound
Timeout
Wait

Discuss Question

Answer: Option A. -> Lock timeout

Lock timeoutThe timeout scheme is particularly easy to implement, and works well if transactions are short and if longwaits are likely to be due to deadlocks.

Question 2. A attribute in a relation is a foreign key if the _______ key from one relation is used as an attribute in that relation .

Candidate
Primary
Super
Sub

Discuss Question

Answer: Option B. -> Primary

PrimaryThe primary key has to be referred in the other relation to form a foreign key in that relation .

Question 3. The relation with the attribute which is the primary key is referenced in another relation. The relation which has the attribute as primary key is called

Referential relation
Referencing relation
Referenced relation
Referred relation

Discuss Question

Answer: Option B. -> Referencing relation

Referencing relation

Question 4. Which one of the following cannot be taken as a primary key ?

Id
Register number
Dept_id
Street

Discuss Question

Answer: Option D. -> Street

StreetStreet is the only attribute which can occur more than once.

Question 5. The ______ is the one in which the primary key of one relation is used as a normal attribute in another relation .

Referential relation
Referencing relation
Referenced relation
Referred relation

Discuss Question

Answer: Option C. -> Referenced relation

Referenced relation

Question 6. A _________ integrity constraint requires that the values appearing in specified attributes of any tuple in the referencing relation also appear in specified attributes of at least one tuple in the referenced relation.

Referential
Referencing
Specific
Primary

Discuss Question

Answer: Option A. -> Referential

ReferentialA relation, say r1, may include among its attributes the primary key of another relation, say r2. This attribute is called a foreign key from r1, referencing r2. The relation r1 is also called the referencing relation of the foreign key dependency, and r2 is called the referenced relation of the foreign key.

Question 7. Which one of the following is a set of one or more attributes taken collectively to uniquely identify a record?

Candidate key
Sub key
Super key
Foreign key

Discuss Question

Answer: Option C. -> Super key

Super keySuper key is the superset of all the keys in a relation.

Question 8. A _____ is a property of the entire relation, rather than of the individual tuples in which each tuple is unique.

Rows
Key
Attribute
Fields

Discuss Question

Answer: Option B. -> Key

KeyKey is the constraint which specifies uniqueness.

Question 9. The subset of super key is a candidate key under what condition ?

No proper subset is a super key
All subsets are super keys
Subset is a super key
Each subset is a super key

Discuss Question

Answer: Option A. -> No proper subset is a super key

No proper subset is a super keyThe subset of a set cannot be the same set.Candidate key is a set from a super key which cannot be the whole of the super set

Question 10. Consider attributes ID , CITY and NAME . Which one of this can be considered as a super key ?