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WorksheetsQuery Processing and Optimization
Total questions: 50
Worksheet time: 42mins
Name
Class
Date
1.
_________ refers to the range of activities involved in extracting data from a database
a)
Query Optimization
b)
Query Processing
c)
Parsing
d)
Query Evaluation
2.
The steps involved in processing __________
a)
Parsing and translation
b)
Optimization
c)
Evaluation
d)
All of Given
3.
In query processing, system must first translate given query into which form?
a)
Internal form
b)
Physical form
c)
high level form
d)
New form
4.
In generating the internal form of the query, the parser checks ___________
a)
Syntax of query
b)
Verifies relation name
c)
None of given
d)
Both of Given
5.
Match the following:
A) evaluation primitive
B) query-execution plan
c) query-execution engine
1) takes a query-evaluation plan, executes that plan, and returns the answers to the query
2) A relationalalgebra operation annotated with instructions on how to evaluate it
3)A sequence of primitive operations that can be used to evaluate a query
a)
A-2, B-3, C-1
b)
A-1, B-3, C-2
c)
A-3, B-1, C-2
d)
A-3, B-2, C-1
6.
Which statement(S) is/are true?
A) A query could be expressed in SQL several different ways.
B) SQL query can be translated into a relationalalgebra expression in one of several ways.
C) There are several ways to evaluate relational-algebra expressions
D) We can execute each relational-algebra operation by one of several different algorithms.
a)
Only A,B
b)
Only A,C,D
c)
Only D
d)
All A,B,C,D
7.
____________ is the process of selecting the most efficient query-evaluation plan from among the many strategies usually possible for processing a given query, especially if the query is complex.
a)
Query Processing
b)
Regulary Expression
c)
Query Optimization
d)
SQL
8.
Query-evaluation plan that minimizes the cost of query evaluation is a duty of _____.
a)
Database System
b)
Database User
c)
Database Admin
d)
Programmer
9.
___________ defines exactly what algorithm should be used for each operation, and how the execution of the operations should be coordinated
a)
Query Engine
b)
Evaluation plan
c)
Query Optimizer Engine
d)
Expression tree
10.
Given a relational-algebra expression, it is the job of __________ to come up with _________ that computes the same result as the given expression, and is the least-costly way of generating the result
a)
query optimizer, expression tree
b)
query evaluation engine, expression tree
c)
query optimizer, query-evaluation plan
d)
query evaluation engine, query evaluation plan
11.
A user executes a query which the ___ system uses to generate the internal form of the query. In addition to checking the syntax of the query, the ___ verifies the name of the relation in the database, then the tuple, then the attribute value.
a)
Parser and translator
b)
Translation
c)
Optimization
d)
Evaluation
12.
What is true about query optimization?
a)
The cost of evaluating a query can vary depending on its type.
b)
The evaluation plan is built by the system, so the user need not focus on writing their query efficiently.
c)
An efficient query evaluation plan is generated by a database system, which minimizes its costs.
d)
a, b and c
13.
If the query was expressed in terms of a view, the _____ phase also replaces all uses of the view by the relational-algebra expression that defines the view.
a)
Pairing
b)
Parsing
c)
Translation
d)
Evaluation
14.
Evaluation Primitive(s) is/are made up of:
a)
Relational algebra operation(s)
b)
Annotation of Instruction
c)
QEP
d)
PipelIne
15.
A sequence of primitive operations that can be used to evaluate a query is known as_______
a)
Query Evaluation plan
b)
Optimization chart
c)
Query Processing plan
d)
Parsing query
16.
The optimizer needs to generate alternative plans that produce the ___________ as the given expression, and to choose the least-costly one.
a)
partially different result
b)
rows as result
c)
columns as result
d)
same result
17.
Grants privileges on SQL authorization mechanism works on____________.
a)
Entire relation
b)
Specified tuples
c)
Specified attributes
d)
Both A and C
18.
which statement is used to revoke an authorization?
a)
Revoke
b)
Modify
c)
Alter
d)
Define
19.
Collections of operations that form a single logical unit of work are called _______.
a)
Views
b)
Networks
c)
Units
d)
Transactions
20.
Authentication refers to :
a)
methods of restricting user access to system
b)
Establishing Identity
c)
controlling the operation on the data
d)
all of the above
21.
Prevention of access to database by Unauthorized Users is refered as
a)
Data Integrity
b)
Data Productivity
c)
Data Security
d)
Data Reliability
22.
___________ may be transmissible from system to system
a)
Authentication
b)
Access Control
c)
Security
d)
None of the Above
23.
In authorization graph if DBA provides authorization to u1 which in turn gives to u2 which of the following is correct ?
a)
If DBA revokes authorization from u1 then u2 authorization is also revoked
.
b)
If u1 revokes authorization from u2 then u2 authorization is revoked
c)
If DBA & u1 revokes authorization from u1 then u2 authorization is also revoked
d)
If u2 revokes authorization then u1 authorization is revoked
24.
_______________ is a technique of granting permission to authorized user to carry out particular transaction
a)
Integrity
b)
Productivity
c)
Security
d)
Authorization
25.
Which form of Authorization allows the user only to read data?
a)
Update Access
b)
Read Access
c)
Insert Access
d)
Both A and B
26.
Which of the following is the Form of Authorization Access?
a)
Read Access
b)
Update Access
c)
Delete Access
d)
All of the above
27.
Which Role in Authorization can execute some data administration command like restore or Upgrade a database?
a)
System Administrator
b)
System Control
c)
Both A & B
d)
System Monitor
28.
With the Help of _______________,User can check his Credentials by him self by entering login id & Password in any Examination System.
a)
Authentication
b)
Productivity
c)
Security
d)
Authorization
29.
MAC means ________.
a)
Manual Acceptance Control
b)
Mandatory Access Control
c)
Mandatory Acceptance Control
d)
Manually Allowance Control
30.
Which is the lower level of System Control Authority?
a)
System Maintenance
b)
System Administrator
c)
System Control
d)
System Monitor
31.
The Usual way of supplying access control to a database is depending on ______________&_____________ priviledges within database
a)
Granting & Revoking
b)
Logging & Logging off
c)
Update & Tampering
d)
Both A & B
32.
What is used if any tampering with the database is suspected?
a)
Database Locking
b)
Database Audit
c)
Database Updation
d)
Database Prevention
33.
We can recover the lost transaction using___________
a)
System Control
b)
System Monitor
c)
Authorization
d)
Audit trail
34.
Which form of access control enables data owners to extend access rights to other logons?
a)
MAC
b)
DAC
c)
Role-based (RBAC)
d)
Rule-based (RBAC)
35.
A security manager is setting up resource permissions in an application. The security manager has discovered that he can establish objects that contain access permissions, and then assign individual users to those objects. The access control model that most closely resembles this is:
a)
Access matrix
b)
Mandatory access control (MAC)
c)
Discretionary access control (DAC)
d)
Role based access control (RBAC)
36.
What is Used to define Access Permission?
a)
Access matrix
b)
DAC
c)
System Control
d)
Authorization
37.
______________is the default access Control mechanism for most desktop operating system
a)
MAC
b)
Role based access control (RBAC)
c)
DAC
d)
Rule-based (RBAC)
38.
Which Security Strategy is generally used in government and military services?
a)
MAC
b)
Role based access control (RBAC)
c)
DAC
d)
Rule-based (RBAC)
39.
Role Based Access Control is also known as___________
a)
Rule-based
b)
Non discretionary access control
c)
discretionary access control
d)
None of the above
40.
Which one of the Following is True for DAC ?
i. Users can transfer their object ownership to another user.
ii. The access type of other users can be determined by the user.
iii. Authorization failure can restrict the user access after several failed attempts.
iv. Unauthorized users will be blind to object characteristics called file size, directory path, and file name.
a)
I and II
b)
I and IV
c)
I,II and III
d)
I,II,III and IV
41.
_______ has an enforced operating system that can label and delineate incoming application data.
a)
MAC
b)
Role based access control (RBAC)
c)
DAC
d)
Rule-based (RBAC)
42.
Under ____________access is allowed or denied to resource objects based on a set of rules defined by a system administrator
a)
MAC
b)
Role based access control (RBAC)
c)
DAC
d)
Rule-based (RBAC)
43.
When a particular account or group attempts to access a resource, the operating system checks the rules contained in the _______ for that object.
a)
System Control List
b)
Mandatory access control List (MACL)
c)
Access Control Lists (ACL)
d)
Authorization List
44.
Role Based Access Control grants access based on a user’s role and implements key security principles such as _____ and_____
a)
least privilege and separation of privilege
b)
position and location
c)
central authority regulations and user-specified rules
d)
assigning access rights and user-specified rules
45.
RBAC is known as ________.
a)
Rule Based Access Control
b)
Non-Discretionary Access Control.
c)
Rule Based Accepted Control
d)
Non-Disable Access Control.
46.
Rule1: Subject given security level may not read any object at higher security level.
Rule2: Subject given security level may not write any object at lower security level.
Above stated rules are respectively identified as which property?
a)
Integrity and Security
b)
Security and Integrity
c)
Security and Star
d)
Star and Security
47.
Which statements are true for Role based access control (RBAC) rules ?
1) It restricts database access based on a person's role within an organization.
2) The roles in RBAC refer to the levels of access that employees have to the
Network.
3)Employees are only allowed to access the information necessary to
effectively perform their job duties.
4) Lower-level employees usually do not have access to sensitive data if they do not need it to fulfil their responsibilities.
a)
Only 1 and 2
b)
Only 1 and 3
c)
Only 3 and 4
d)
All 1,2,3 and 4
48.
With the rule-based model, __________ sets access management rules that can allow or deny user access to specific areas, regardless of an employee’s other permissions.
a)
security professional
b)
system administrator
c)
system manager
d)
A or B
49.
With the Help of _.................,User can check his Credentials by him self by entering login id & Password in any Examination System
a)
Authentication
b)
Security
c)
Authorization
d)
System control
50.
Which statements are true?
1) Data security deals with protection of data.
2) Data integrity deals with the validity of data.
3) Data integrity is making sure the data is correct and not corrupt.
4) Data security refers to the making sure that data is accessed by its intended users, thus ensuring the privacy and protection of data.
a)
Only 1 and 2
b)
Only 1 and 3
c)
Only 2 and 3
d)
all statements are true
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