Database Management System

Four DML commands are:

View is a:

The different levels of data abstraction are:

Which of the following is true?

What is the purpose of project operation:

The weak entity set does not have sufficient attributes to form.

Which normal form is considered adequate for normal relational database design?

Which of the following is not a super key in R(V, W, X, Y, Z) with primary key VY?

Consider R (A, B, C, D, E) with following FDs:- $ A \rightarrow B $, $ A \rightarrow C $, $ CD \rightarrow E $, $ B \rightarrow D $, $ E \rightarrow A $ which of the following FDs is not implied by above set?

Which of the following is a concurrency control protocol.

What is attribute closure $ X^+ $ of a set of attributes X with respect to a set of FDs F? Give the algorithm for commuting $ X^+ $ for X.

Relation R (ABCDEFGH) contains only atomic values for all of its attributes. $ F = \{ CH \rightarrow G, A \rightarrow BC, B \rightarrow CFH, E \rightarrow A, F \rightarrow EG \} $ is a set of functional dependencies (FDs) so that F is exactly the set of FDs that hold for R.
(i) Find all the candidate keys the relation R have?
(ii) Find the highest normal form with justification in which R exist?

Briefly explain the ACID properties of the transactions to ensure integrity of the data.

Consider the transactions T1, T2 and T3 and schedules S1 and S2 given below:
T1: r1 (X); r1(Z); w1 (X); w1 (Z)
T2: r2 (Y); r2 (Z); w2 (Z)
T3: r3 (Y); r3 (X); w3 (Y)
S1: r1 (X); r3(Y); r3(X); r2 (Y); r2(Z); w3(Y); w2 (Z); r1 (Z); w1(X); w1 (Z).
S2: r1 (X); r3 (Y); r2(Y); r3(X); r1(Z); r2(Z); w3 (Y); w1 (X); w2(Z); w1 (Z).
Determine which of the above schedules are conflict - serializable.

Explain the reasons for the update, insertion and deletion anomalies.

With example discuss candidate key, super key, primary key and foreign key.

What are the typical phases of query processing? With a sketch, discuss these phases in high level query processing.

When is the decomposition of relation schema R into two relation schemes X and Y, said to be a loss-less-join decomposition? Why is this property so important? Explain with example.

Explain the terms partial functional dependency' and 'transitive dependency'. Define 2NF and 3 NF in relation with these terms.

Discuss the concept of generalization, specialization and aggregation.

Consider the following employee database, primary keys are underlined.
Employee (ename, street, city)
Works (ename, cname, salary)
Company (cname, city)
Manages (cname, manager-name)
Write SQL queries to:
(i) Find the names of all the employees who work for XYZ.
(ii) Find all employees who live in the same city as the company for which they work.
(iii) Find all employees who live in the same cities and on the same streets as do their managers.
(iv) Find all employees who earn more than the average salary of all employees of their company.

Discuss the advantages and disadvantages of using DBMS as compared to a conventional file system.

What is weak entity set? Explain with suitable example. How weak entities are represented as relational schemas.

Four DML commands are:

View is a:

The different levels of data abstraction are:

Which of the following is true?

What is the purpose of project operation:

The weak entity set does not have sufficient attributes to form.

Which normal form is considered adequate for normal relational database design?

Which of the following is not a super key in R(V, W, X, Y, Z) with primary key VY?

Consider R (A, B, C, D, E) with following FDs:- $A \rightarrow B$, $ A \rightarrow C $, $ CD \rightarrow E $,$ B \rightarrow D $,$ E \rightarrow A $ which of the following FDs is not implied by above set?

Which of the following is a concurrency control protocol.

What is attribute closure $X^+$ of a set of attributes X with respect to a set of FDs F? Give the algorithm for commuting $X^+$ for X.

Relation R (ABCDEFGH) contains only atomic values for all of its attributes. $ F = { CH \rightarrow G, A \rightarrow BC, B \rightarrow CFH, E \rightarrow A, F \rightarrow EG } $ is a set of functional dependencies (FDs) so that F is exactly the set of FDs that hold for R.
(i) Find all the candidate keys the relation R have?
(ii) Find the highest normal form with justification in which R exist?

Briefly explain the ACID properties of the transactions to ensure integrity of the data.

Consider the transactions T1, T2 and T3 and schedules S1 and S2 given below:
T1: r1 (X); r1(Z); w1 (X); w1 (Z)
T2: r2 (Y); r2 (Z); w2 (Z)
T3: r3 (Y); r3 (X); w3 (Y)
S1: r1 (X); r3(Y); r3(X); r2 (Y); r2(Z); w3(Y); w2 (Z); r1 (Z); w1(X); w1 (Z).
S2: r1 (X); r3 (Y); r2(Y); r3(X); r1(Z); r2(Z); w3 (Y); w1 (X); w2(Z); w1 (Z).
Determine which of the above schedules are conflict - serializable.

Explain the reasons for the update, insertion and deletion anomalies.

With example discuss candidate key, super key, primary key and foreign key.

What are the typical phases of query processing? With a sketch, discuss these phases in high level query processing.

When is the decomposition of relation schema R into two relation schemes X and Y, said to be a loss-less-join decomposition? Why is this property so important? Explain with example.

Explain the terms partial functional dependency' and 'transitive dependency'. Define 2NF and 3 NF in relation with these terms.

Discuss the concept of generalization, specialization and aggregation.

Consider the following employee database, primary keys are underlined.
Employee (ename, street, city)
Works (ename, cname, salary)
Company (cname, city)
Manages (cname, manager-name)
Write SQL queries to:
(i) Find the names of all the employees who work for XYZ.
(ii) Find all employees who live in the same city as the company for which they work.
(iii) Find all employees who live in the same cities and on the same streets as do their managers.
(iv) Find all employees who earn more than the average salary of all employees of their company.

Discuss the advantages and disadvantages of using DBMS as compared to a conventional file system.

What is weak entity set? Explain with suitable example. How weak entities are represented as relational schemas.

• SQL Injection
• Two-phase locking protocol
• Object Oriented DBMS
• Armstrong's Axioms

Choose the correct answer from the following (any seven) :

a) List five responsibilities of the database manager. For each responsibility, explain the problem that would arise if the responsibility were not discharged. b) Consider a two-dimensional integer array of size name that is to be used in your favourite programming language. Using the array as an example, illustrate the difference (i) between the three levels of data abstraction and (ii) between a schema and instances.

Construct an E-R diagram for a car insurance company that has a set of customers, each of whom owns one or more cars. Each car has associated with it zero to any number of recorded accidents.

a) What are DDL and DML? Explain with the help of examples. b) Explain the following operations with the help of examples : (i) Set of intersection operation (ii) Natural join operation (iii) Division operation

a) What are the differences between primary index and secondary index? b) How does the remapping of bad sectors by disk controllers affect data retrievals rates?

Show that the two-phase locking protocol ensures conflict serializability and that transaction can be serialized according to their lock points.

a) Make a list of security concerns for a bank. For each item on your list, state whether this concern relates to physical security, human security, operating-system security or database security. b) Explain web and distributed database with the help of example.

Consider the following ordering schedule—'S' of transactions: T1 : R(A); T1 : A:=A+5; T1 : commit; T2 : R(B); T2 : B:=B+5; T3 : R(C); T3:C:=C+5; T3 : C:=C+5; T4 : R(A); T4 : A:=A+5; T4 : R(D); T4 : D:=D+5; T4 : commit; T2 : commit; T3 : commit; Let the initial value of A=B=C=D=0. The system follows log-based recovery process of immediate database modification. The assumption is the concurrency control system uses strict 2PL, and all the transactions share a common disk buffer and single log. Explain what happens during the recovery process, if it occurs a failure at 'T2 : commit' statement.

Write a short note on any one of the following : a) SQL injection b) Database recovery

The way a particular application views the data from the database that the application uses is a

A relational database developer refers to a record as

Key to represent relationship between tables is called

It is better to use files than a DBMS when there are

Which of the following are the five built-in functions provided by SQL?

A B-tree of order 4 and of height 3 will have a maximum of keys.

Consider the following action: TRANSACTION..... Commit; ROLLBACK; What does rollback do?

Which of the following is used to get back all the transactions back after rollback?

_____ is an attack which forces an end user to execute unwanted actions on a Web application in which he/she is currently authenticated.

_____ allows a system administrator to associate a function with a relation; the function returns a predicate that must be added to any query that uses the relation.

What are the five main functions of a database administrator?

What are four main differences between file-processing system and a DBMS?

Construct an E-R diagram for a university registrar's office. The office maintains data about each class, including the instructor, the enrollment, and the time and place of the class meetings. For each class pair, a grade is recorded. Document all assumptions that you make about the mapping constraints.

What is the use of relational query language in DBMS? Use the example to explain tuple and domain relational calculus.

Explain the following operations with the help of examples: (i) Generalized projection (ii) Outer join (iii) Aggregate function

Construct the B+ tree for the following set of key values: (2, 3, 5, 7, 11, 17, 19, 23, 29, 31). Assume that tree is initially empty and values are added in ascending order. Construct B+ tree for the cases where the number of pointers that will fit in one node is as follows: (a) Four (b) Six (c) Eight

List the ACID properties. Explain the usefulness of each.

What benefit is provided by rigorous two-phase locking? How does it compare with other forms of two-phase locking?

What is the purpose of having separate categories for index authorization and resource authorization?

Explain the data mining and data warehousing related to DBMS.

Compute the closure (F+) of the following set of functional dependencies for the relational schema (A, B, C, D, E) = R. List the candidate keys for R:
$ A \rightarrow BC $
$ CD \rightarrow E $
$ B \rightarrow D $
$ E \rightarrow A $

The way a particular application views the data from the database that the application uses is a

A relational database developer refers to a record as

Key to represent relationship between tables is called

It is better to use files than a DBMS when there are

Which of the following are the five built-in functions provided by SQL?

A B-tree of order 4 and of height 3 will have a maximum of keys.

Consider the following action: TRANSACTION..... Commit; ROLLBACK; What does rollback do?

Which of the following is used to get back all the transactions back after rollback?

_____ is an attack which forces an end user to execute unwanted actions on a Web application in which he/she is currently authenticated.

_____ allows a system administrator to associate a function with a relation; the function returns a predicate that must be added to any query that uses the relation.

What are the five main functions of a database administrator?

What are four main differences between file-processing system and a DBMS?

Construct an E-R diagram for a university registrar's office. The office maintains data about each class, including the instructor, the enrollment, and the time and place of the class meetings. For each class pair, a grade is recorded. Document all assumptions that you make about the mapping constraints.

What is the use of relational query language in DBMS? Use the example to explain tuple and domain relational calculus.

Explain the following operations with the help of examples: (i) Generalized projection (ii) Outer join (iii) Aggregate function

Construct the B+ tree for the following set of key values: (2, 3, 5, 7, 11, 17, 19, 23, 29, 31). Assume that tree is initially empty and values are added in ascending order. Construct B+ tree for the cases where the number of pointers that will fit in one node is as follows: (a) Four (b) Six (c) Eight

List the ACID properties. Explain the usefulness of each.

What benefit is provided by rigorous two-phase locking? How does it compare with other forms of two-phase locking?

What is the purpose of having separate categories for index authorization and resource authorization?

Explain the data mining and data warehousing related to DBMS.

Compute the closure (F+) of the following set of functional dependencies for the relational schema (A, B, C, D, E) = R. List the candidate keys for R:
$ A \rightarrow BC $
$ CD \rightarrow E $
$ B \rightarrow D $
$E \rightarrow A$

• RBAC model
• Concurrency control