MS Computer Science Virtual University of Pakistan

CS-712 Distributed Database Management System Viva

CS-712 Distributed Database Management System Viva Preparation

Question.    Vertical fragmentation

Answer:- Vertical fragmentation divides the relation into attributes called columns.

Question.   Horizontal fragmentation

Answer:- Horizontal Fragmentation divides the relation into tuples called rows.

Types of Horizontal Fragmentation

Primary and derived

Question.    what will be distributed in distributed database Management system?

Answer:-Database will be distributed using one o two different approaches Replication or fragmentation

Question.    First Normal Form?

Every attribute is single valued for each tuple.

Question.    2nd Normal Form?

2nd Normal Form if it is in 1st Normal Form

Question.    3rd Normal Form?

Answer:-3 normal forms is the third step in normalizing a database and it builds on the 1st an 2nd normal form.

Question.      Transitive dependency?

Answer:-   is a functional dependency a transitive dependency can occur only in a relation that has three or more attributes. 

Question.     partial dependency?

Answer:- Partial dependency means that a nonprime attribute is functionally dependent on part of a candidate key.

Question.    Fragmentation

Answer:- Fragmentation occurs naturally when we use a disk frequently, creating, deleting, and modifying files.

 

Question.   Predicates

Answer:- this function returns true or false value based on condition like p: y? {true, false}

Question.    ring topology

Answer:- each node connects to exactly two other nodes               

Question.    peer to peer

Answer:- is a distributed application architecture that partitions tasks between peers

Question.    Client Server Architectures

Answer:- Client-server architecture (client/server) is a network architecture in which each computer or process on the network is either a client or a server.

Question.   Simple Predicates

Answer:- The simple predicate is the main verb in the predicate that tells what the subject does.

Question.    Heterogeneity

Answer:- applications need to be developed (or ported) to each device and maintained separately for each device.

Question.     difference between equi join and natural join?

Answer:- Equi join only have equality (=) operator in the join condition

A NATURAL JOIN is a JOIN operation that creates an implicit join clause for you based on the common columns in the two tables.

Question.    Dis joints

Answer:- two sets are said to be disjoint sets if they have no element in common