CS403 old past paper 2010 spring


FINALTERM  EXAMINATION
Spring 2010
CS403- Database Management Systems
Marks: 58

Question No: 2     ( Marks: 1 ) - Please choose one
Which of the following statements are Data Definition Language command?
INSERT
UPDATE
GRANT
       ► TRUNCATE



Question No: 3     ( Marks: 1 ) - Please choose one
Which of the following statements is true about the views?
view is always a complete set of all the tables in a database
View can not be used for retrieving data
The results of using a view are not permanently stored in the database.
Rows can not be updated or deleted in the view
Question No: 4     ( Marks: 1 ) - Please choose one
How many clustered index(es) do each database table have?
2
3
5
       ► 1
Question No: 5     ( Marks: 1 ) - Please choose one
Suppose there are 4 rows and 3 columns in TABLE1 and 6 rows and 5 coulmns in TABLE2;what is the size of the cartesian product incase of CROSS JOIN between these two tables?
       ► 24
                                 20
18
15


Question No: 6     ( Marks: 1 ) - Please choose one
Which of the following is not one of the properties of Transaction?
atomicity
consistency
       redundancy
durability
Question No: 7     ( Marks: 1 ) - Please choose one
Which of the following is INCORRECT about VIEWS?
It is not possible to left out the data which is not required for a specific view.
A database view displays one or more database records on the same page.
Views can be used as security mechanisms
Views are generally used to focus the perception each user
has of the database.
Question No: 8     ( Marks: 1 ) - Please choose one
Which of the following gives all the fields from employee table named as EMP?
       select * from EMP;
select emp* from EMP'
select emp_id where EMP;
select * where EMP;

   
Question No: 9     ( Marks: 1 ) - Please choose one

Consider the relation Interview(CandidateNo, InterviewDate, InterviewTime, StaffNo, RoomNo) and the following functional dependencies.
FD1 : CandidateNo, InterviewDate -> InterviewTime, StaffNo, RoomNo FD2 : RoomNo, InterviewDate, InterviewTime -> StaffNo, CandidateNo FD3 : StaffNo, InterviewDate -> RoomNo
Which of the following is correct?
The relation Interview is in 3NF
       The relation Interview is in BCNF.
The FD3 violates 3NF.
The FD2 violates 2NF.
Question No: 10     ( Marks: 1 ) - Please choose one
Which of the following types of partitioning reduces the chances of unbalanced partitions?
vertical
List
Hash
Range
Hash Partitioning:
It is a type of horizontal partitioning. In this type particular algorithm is applied and
DBMS knows that algorithm. So hash partitioning reduces the chances of unbalanced partitions to a large extent Question No: 11                    ( Marks: 1 ) - Please choose one Which of the following is one of the purposes of using DDL commands?
inserting records into databases
updating records into databases
manipulating databases
creating and destroying databases

Question No: 12     ( Marks: 1 ) - Please choose one
Which of the following statements creates a database named COMPANY.
CREATE DATABASE company
CREATE DB company
ADD DATABASE copmany
CREATE company DATABASE
Question No: 13     ( Marks: 1 ) - Please choose one
What is the impact of setting multiple indexes for the same key, in index sequential files?
Multiple indexes for the same key can not be set
       ► It increases efficiency
It decreases efficiency
It will increase complexity as the access time will be increased
New records are added to an overflow file
Record in main file that precedes it is updated to contain a pointer to the new record
The overflow is merged with the main file during a batch update Multiple indexes for the same key field can be set up to increase
efficiency
Question No: 14     ( Marks: 1 ) - Please choose one
Consider a transaction which includes following operations
Z= Z + 10
Write Z
...
Suppose that the value of Z after addition and the execution of this operation is 17. Now
against the write operation the entry made in the log file will be
What does Z reflects in the above entry?
Object being updated
Identity of the transaction
Object value
Identity of the next transaction to be executed
In the entry, Tn reflects the identity of the transaction, Z is the object being updated and 33 is the value that has to be placed in Z.


Question No: 15     ( Marks: 1 ) - Please choose one
Which of the following is not true regarding DB transactions?
A set of database operations that are processed partly
A database transaction is a logical unit of database operations
A database transaction must be atomic
A database transaction must contains the ACID property
The transaction-processing system ensures that either all operations in a transaction are completed without error, or none of them are. If some of the operations are completed but errors occur when the others are attempted, the transaction-processing system “rolls
back” all of the operations of the transaction (including the successful ones), thereby erasing all traces of the transaction and restoring the system to the consistent, known state that it
was in before processing of the transaction began. If all operations of a transaction are completed successfully, the transaction is committed by the system, and all changes to the database are made permanent; the transaction cannot be rolled back once this is don
Question No: 16          ( Marks: 1 ) - Please choose one
Which of the following is not true about input forms?
Provide an easy, effective, efficient way to enter data into a table
Especially useful when the person entering the data is not familiar with the inner workings
Provide different controls to add data into the tables
       ► One input forms can populate one table at a time Question No: 17     ( Marks: 1 ) - Please choose one Which of the following is an example of volatile memory?
       ► RAM
ROM
Flash memory
CPU
Question No: 18     ( Marks: 1 ) - Please choose one
Which of following is NOT generally the aim of data partitioning and placement of data?
Reduce Workload
Balance Workload
       ► Merging different relations
Speed up rate of useful works.
Question No: 19     ( Marks: 1 ) - Please choose one
ALTER TABLE exams
RENAME COLUMN Q_description TO Question_Descp, Std_ID to Student_ID. Syntax of ALTER TABLE is NOT correct.
True
False
Question No: 20     ( Marks: 1 ) - Please choose one
Which of the following is Advantage of Re-Hashing technique to handle the collisions?
Collisions dont use primary table space
Unlimited number of elements
       ► Fast access through use of main table space (page29 vuzs)
Overhead of multiple linked lists
Question No: 21     ( Marks: 1 ) - Please choose one
Materialized views and Indexes are NOT similar by the following way(s).
They consume storage space
                                 They must be refreshed when the data in their master tables changes.
       ► They can be accessed directly using a SELECT statement
All of the Given
Unlike indexes, materialized views can be accessed directly using a SELECT statement.
Question No: 22     ( Marks: 1 ) - Please choose one
Select 'NORTH', CUSTOMER From CUST_DTLS Where REGION = 'N' Order
By
CUSTOMER Union Select 'EAST', CUSTOMER From CUST_DTLS Where
REGION = 'E' Order By CUSTOMER
The above statement:
Has an error - the string should be in double quotes.
Has an error - ORDER BY clause.
Does not have an error.
Has an error - the string in single quotes 'NORTH' and 'SOUTH'.
Question No: 23     ( Marks: 1 ) - Please choose one
A software package designed to store and manage databases
Database
       ► DBMS
Data model
Data
A Database Management System (DBMS) is a software package designed to store and manage databases. Database Management Systems
Question No: 24     ( Marks: 1 ) - Please choose one
Who is responsible for authorizing access to the database, for coordinating and monitoring its use ?
Database Designers
       ► Database Administrators
End Users
Application Programmers
Question No: 25     ( Marks: 1 ) - Please choose one
A superkey that does not contain a subset of attributes that is itself a superkey is called a
candidate key
primary key
superkey
secondary key
Question No: 26     ( Marks: 1 ) - Please choose one
A       _ entity has a primary key that is partially or totally derived from the parent entity in the relationship.
strong
weak
business
relationship
A weak entity has a primary key that is partially or totally derived from the parent entity in the relationship
Question No: 27     ( Marks: 2 )
What is the data type?

A data type (or datatype) In programming, a classification identifying one of various types of data, as floating-point, integer, or Boolean, stating the possible values for that type, the operations that can be done on that type, and the way the values of that type are stored. Question No: 28       ( Marks: 2 )
Which DML statement changes the values of one or more columns based on some conditions.
Update command
Question No: 29     ( Marks: 2 )
Name the two types of caching that are commonly used in personal computers? Two types of caching are commonly used in personal computers: memory caching and disk caching
Question No: 30     ( Marks: 2 )
What is Serial Execution?
Serial execution is an execution where transactions are executed in a sequential order,
that is, one after another. A transaction may consist of many operations. Serial execution means that all the operations of one transaction are executer first, followed by all the operations of the next transaction and like that.
Question No: 31     ( Marks: 3 )
Write three benefits of using VIEWS.

1.       They work as table and, provide security from unauthorized access.

2.       updated automatically when some changes occurs in original table

3.       views give a group of users access to just the information they are allowed to


Question No: 32     ( Marks: 3 )
Shortly explain BYTE data field?
Some of more frequently supported numeric data types include Byte, Integer, and Long
Integer. Each of these types supports different range of numeric values and takes 1, 4 or 8 bytes to store. Now, if we declare the age attribute as Long Integer, it will definitely serve the purpose, but we will be allocating unnecessarily large space for each attribute. A Byte type would have been sufficient for this purpose since you wont find students or employees of age more than 255, the upper limit supported by Byte data type.
Question No: 33     ( Marks: 3 )
State the main purpose of index in relation with the queries executions.
It will help searching the required data by directly accessing it via index.
Question No: 34     ( Marks: 5 )
Differentiate between the cluster index and non cluster index ?
1 A cluster index is a form of tables which consist of column and rows.
2 Cluster index exists on the physical level
3 It sorts the data at physical level
4 It works for the complete table
5 There is a whole table in form of sorted data
6 A table can contain only one cluster index
Non Cluster Index

1 A non cluster index is in the form of a report about the tables.
2 They are not created on the physical level but at the logical level
3 It does not sort the data at physical level
4 A table has 255 non clustered indexes
5 A table has many non clustered indexes.
6 It work on the order of data
Question No: 35     ( Marks: 5 )
Consider the two relations,
Department (Dept_Code, Dep_Name,Dept_Head) and
Employee(Emp_ID,Emp_Name, Designation, DoB, Dept).
Write SQL statement to drop the primary key of Department relation? The fields in
Employee should reflect the removal in Department table. Answer:
If you wanted to drop any Primary key column you first have to drop the primary key

constraints and then you can drop the primary key column. (vuzs) ALTER TABLE Department DROP CONSTRAINT Pkzxyx; ALTER TABLE Department DROP COLUMN Dept_code; Question No: 36 ( Marks: 5 )
Briefly explain rollback and rollforward


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