Mid - Important Questions

1. Write a note on fragmentation. Its advantages and disadvantages.
1.1 Vertical and horizontal fragmentation ?
1.2 Rules for correctness.
1.3.1 If fragments can change DDBMS semantic's ?
1.3.2 Write a note on completeness and reconstruction of VF ?
1.4 How can we verify the properties of completeness and reconstruction of a vertical fragmentation?(5)
1.5 How/What completeness of horizontal fragmentation is verified ?
1.6 About Horizontal Fragmentation, Owner and member relation.
1.7 Differentiate between VF and HF OR(PHF or VHF)
1.8 Do PHF of empky table Location wise
3. Write a note on need for distributed database. Why it's more beneficial? What is meant by optimality?
4. What are complete predicates? Minterm predicates?
5. Write the formula to calculate affinity matrix?
5.1 Draw CA(clustered affinity ) along with Affinity matrix ( lect 19 )
5.1.1 Convert AA into CA (10 marks)
5.2 To make affinity matrix. Describe the contribution of moving attribute A4 between A1 and A2.
5.3 Affinity matrix for given queries, and contribution of moving column 3 between column 1 and column 2.
5.4 Attribute Usage Matrix for given queries
5.5 (Case)
Consider the relation Student (stID, stName, stAdr,prName,curSem)
Three application access the relation through following three queries respectively
q1. Select stID, stName, curName, from student
q2. Select stID, stName, stAdr from student where stId = value
q3. Select stName,prName from Student
Find the affinity matrix

6. Explain (A1, D2, H1) (A1, D0, H1) architectures of DBMS.
7. What is autonomy? What are its types? How it's classified?
8. How we remove transitive dependency?
9.  Describe software component of replication? ( lect 21 )
9.1 Name the software used for replication (5)
9.2 Discuss the disadvantages of replication ?
9.3 Describe SQL Server tools involves In replication.
9.4 Differentiate between fully and partially databases
9.5 Differentiate b/w Non-Replicated Databases and Partitioned Database (5 marks)
10. Why distributed database system’s performance is better than centralized database system.(5)
11. Key differences between LAN and WAN
12 DDBMS Components their working and Interfacing
12.2 Independences of Distributed Database
12.3 Write ways of user access data from DDBMS?
12.4 Inputs needs for distributed database
12.5 How the distributed databases are connected.
12.6 Global schema importance in DDBS.
13.  Star and bus topology
13.1 Differentiate between Bus and ring Topology
14.classification criteria of computer network.
14.1 classify the computer networks?
15. what is Primary and secondary key n composite n super key difference?
16. What is the purpose of integrity rules? How they are enforced on the database?(5 marks)
17. Components of relational data model.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.

MCQS

The database environment has all of the following components except: ___Users_____
A table or file is broken down in different parts and stored at different locations is called ___Fragmentation___
The _____Set-difference______ operation, denoted by " − ", allows us to find tuples that are in one relation but are not in another.
Physical or logical arrangement of network is____Topology______
Database architecture can be discussed in ______3________ dimensions.
Which term is used with distributed databases storage __Both Replication and Fragmentation__ ?
For derived horizontal fragmentation _____3____ inputs are required.
Bond energy algorithm has been designed to determine ______Groups_____.
The computation time of the Clustering algorithm is ______On2________.
Hybrid Fragmentation combines _Horizontal, vertical fragmentation_.

Important Topics

Reasons for fragmentation (70) 13

Fragmentation independence refers to the ability of end users to store logically related information at different physical locations. There are two types of fragmentation independence: vertical partitioning and horizontal partitioning. Horizontal partitioning permits different rows of the same table to be stored at different remote sites. This is commonly done by organizations that maintain several branch offices, each with an identical set of table structures. 

Vertical partitioning refers to the ability of a distributed system to fragment information such that the data columns from the same logical tables are maintained across the network. Oracle accomplishes this with Oracle views that hide specific columns and rows in a table.

Generation of clustered affinity matrix (CA) is done in three steps:

1.  Initialization. Place and fix one of the columns of AA arbitrarily into CA. Column 1 was

chosen in the algorithm.

2.  Iteration. Pick each of the remaining n-I columns (where I is the number of columns

already placed in CA) and try to place them in the remaining i+1 positions in the CA

matrix. Continue this step until no more columns remain to be placed. 

3.  Row ordering. Once the column ordering is determined, the placement of the rows should

also be changed so that their relative positions match the relative positions of the

columns. 

COM_MIN Algorithm 
Given: a relation R and a set of simple predicates Pr

Output: a complete and minimal set of simple predicates Pr' for Pr

Rule 1: a relation or fragment is partitioned into at least two parts which are accessed differently by at least one application.

Reasons OF DDBMS

• Local units want control over data.
• Consolidate data for integrated decisions
• Reduce telecommunication costs.
• Reduce the risk of telecommunication  failures.

Vertical Fragmentation  and Vertical Fragmentation (85)

Distributed Database Design  (68-70)