Question

In databases one data model is especially common. It’s called Entity-…

Select one:

a. Relationship

b. Relation

c. Connection

d. Fulfillment

e. Equalization

What is the purpose of “degree-two consistency”?

Select one:

a. To avoid cascading aborts without necessarily ensuring serializability.

b. To avoid serializable aborts without necessarily ensuring a cascade.

c. To avoid aborting cascades without serializing ensurability.

d. To abort cascading avoidances without ensuring serializability.

e. To ensure cascading aborts without avoiding serializability

One of the more common buffer replacement strategies is called LRU. What is its meaning?

Select one:

a. Lost, received, uncovered

b. Last record used

c. Latest relation uploaded

d. Least recently used

e. Long RAM usage

Answer 1

1)a) Relationship model

We have many database models like the Hierarchical model, Entity-relationship model, Document model, Object-oriented model, Relational model. The entity-relationship model is suitable for the asked question.

2)Degree two consistency is the concurrency control method. It is to avoid cascading aborts without necessarily ensuring serializability. It works as same as two-phase locking. So "option a" is the answer.

3)LRU is one of the famous page replacement algorithms its full form is Least Recently Used. According to this algorithm whenever a new page needs a frame we need to allocate the new page in the frame which was least recently used. So option d is correct.