FINALTERM EXAMINATION
Spring 2010
CS403- Database Management Systems (Session - 1)
CS403 Question No: 1
Which feature of database provides conversion from inconsistent state of DB to a consistent state ensuring minimum data loss?
► User accessible catalog
► Data processing
► Authorization service
► Recovery service
CS403 Question No: 2
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
CS403 Question No: 3
Which of the following is true about TRUNCATE?
► Can be Rolled back.
► Activates Triggers.
► is DML Command.
► Resets identity of the table.
CS403 Question No: 4
Which of the following will be deleted relating to a table if you use TRUNCATE command?
► all rows in a table
► indexes
► table structure and its columns
► constraints
CS403 Question No: 5
Which of the following is not true about relational tables?
► Column values are of the same kind.
► Each row is unique.
► Each column must have a unique name.
► The sequence of rows is significant.
CS403 Question No: 6
Which of the following is not true about De-normalization?
► It is the process of attempting to optimize the performance of a database
► De-normalization is a technique to move from lower to higher normal forms of database modeling
► In de-normalization it is required to add redundant data.
► It enhances the performance of DB
CS403 Question No: 7
Which of the following is the correct way to find out the size of cartesian product incase of CROSS JOIN?
► the number of columns in the first table multiplied by the number of columns in the second table.
► the number of columns in the first table multiplied by the number of rows in the second table.
► the number of rows in the first table multiplied by the number of columns in the first table.
► the number of rows in the first table multiplied by the number of rows in the second table.
CS403 Question No: 8
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.
CS403 Question No: 9
What is the maximum limit of keys in context with Indexed sequential files?
► 7
► 255
► 1
► 235
CS403 Question No: 10
Structural constraints of a relationship type refer to
► identifying the owner entity type relevant to a given entity type
► whether the existence of an entity depends on it being related to another entity via the
relationship type.
► the role that a participating entity from the entity type plays in each relationship instance.
► the constraints applicable in granting access to tables, columns and views in a database
schema.
CS403 Question No: 11
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
CS403 Question No: 12
Which of the given techniques is/are used to improve query performance in database?
► Good File organization
► Indexing
► Both Indexing and Good File organization
► Select only one record per query
CS403 Question No: 13
While recovering data, which of the following files does a recovery manager examines at first?
► A system file
► Log file
► Data dictionary
► Metadata
CS403 Question No: 14
_______ is a control that users click to perform an action, set or toggle a state, or set an option.
► Button
► Text box
► Input form
► Report
CS403 Question No: 15
_______is a control that enables users to select one option from an associated list; users can also type an option.
► Combo box
► Button
► Text box
► Static area
CS403 Question No: 16
Partitions may become unbalanced in:
► Range partitioning
► Hash partitioning
► List partitioning
► Vertical partitioning
CS403 Question No: 17
Only one type of constraint can be enforced in any table by CREATE command
► True
► False
CS403 Question No: 18
ALTER TABLE exams
ALTER COLUMN Q_description varchar(50)
Syntax of ALTER TABLE is NOT correct.
► True
► False
CS403 Question No: 19
Which of the following is disadvantage of chaining technique to handle the collisions?
► Unlimited Number of elements
► Fast re-hashing
► Overhead of multiple linked lists
► Maximum number of elements must be known
CS403 Question No: 20
In which of the following, Materialized Views are suitable
► Data warehousing
► Decision support
► Mobile computing
► All of the Given
CS403 Question No: 21
A software package designed to store and manage databases
► Database
► DBMS
► Data model
► Data
CS403 Question No: 22
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
CS403 Question No: 23
A ____ relationship exists when an association is maintained within a single entity.
► unary
► ternary
► binary
► weak
CS403 Question No: 24
Which of the following is NOT one of the ways of resolving deadlocks?
► Undoing all the updates made by the particular transaction which is the cause of deadlock.
► A message is passed to the victim and depending on the system the transaction may or may not be started again automatically.
► Picking a list of all previously completed transactions and undoing all the updates.
► Rollback `victim' transaction and restart it.
CS403 Question No: 25
You can’t modify more than one table at a time through a view.
► True
► False
CS403 Question No: 26
Which of the following is one of the purposes of using DML commands?
► Creating databases
► Destroying databases
► Inserting data in tables
► Non of the above
CS403 Question No: 27 ( M a r k s: 2 )
Name the two types of ordered Indices.
- Dense Index
- Sparse Index
CS403 Question No: 28 ( M a r k s: 2 )
State any two problems that can come up as a result of inconsistent database.
- Uncommitted update
- Inconsistent Analysis
CS403 Question No: 29 ( M a r k s: 2 )
Write the main purpose of NOT operator.
It used to negate any logical expression
Example:
Select * from students where Name is Null
Above command will bring all entries where name columns are having null value.
Select * from students where Name is NOT Null;
It will be reverse of our previous command and bring all those records which are not null in name colums.
It simply reverser any expression.
CS403 Question No: 30 ( M a r k s: 2 )
What is ‘Serial Execution’?
It is type of exaction where transitions are run in a sequence.
If we have two transactions first it will complete all the steps of first transaction and then steps of 2nd transaction will step.
A single transaction can consists of multiple steps. Those steps will run in a sequential order.
CS403 Question No: 31 ( M a r k s: 3 )
State the main purpose of index in relation with the queries executions.
- Index help to better recovery and retrieval of record from the database..
- By building index on any attribute will help the queries to improve query performance.
- multiple indexes provide flexibility to retrieve the data from various attributes.
CS403 Question No: 32 ( M a r k s: 3 )
What is the prupose of IN operator?
- It us used to check whether any value fall in given set of values or not.
- work whichwe perform with the help of multiple or condisiton can be easy done via IN operator.
Example: select * from Emp where Dept in (10,20,30);
By the use of IN operator we can get all records for dept = 10 ,20 and 30
We can combine No in operator with In operator to reverse the expression
CS403 Question No: 33 ( M a r k s: 3 )
What effect can be occurred if a transaction lacks durability?
Data can be inconsistence state, suppose if crash happened and in recovery rollback or commit is not possible in absence of durability.
CS403 Question No: 34 ( M a r k s: 5 )
Write the basic syntax of creating an INDEX.
CREATE INDEX indexname ON TableName (Last_Name);
CS403 Question No: 35 ( M a r k s: 5 )
What is the purpose of creating VIEWS in DBMS?
- 1.views can be used as security mechanism.
- 2.Present the data to user of their interest
- 3.Stop the access to unnecessary access to data to irrelevant person
- 4.simplify presentation complex extracted data for example data extracted from the multiple tables to the user.
- 5.updated automatically when any change occur to underlying tables
-
CS403 Question No: 36 ( M a r k s: 5 )
Write an SQL statement which displays a list of persons from the table named PERSON. The complete information of only those person should be displayed whose first name is ALI and the last name is AHMED;
SELECT * FROM Person where FirstName = ‘ALI’ and Lastname = ‘AHMED’;