Explore topic-wise MCQs in Operating System.

This section includes 64 Mcqs, each offering curated multiple-choice questions to sharpen your Operating System knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following is/are the Database server functions?i) Data management ii) Transaction managementiii) Compile queries iv) Query optimization

A. i, ii, and iv only
B. i, ii and iii only
C. ii, iii and iv only
D. All i, ii, iii, and iv
Answer» B. i, ii and iii only
2.

Evaluate the following SQL statements in the given order.Which statement is true regarding the above FLASHBACK operation?

A. It recovers only the first DEPT table
B. It recovers only the second DEPT table
C. It does not recover any of the tables because FLASHBACK is not possible in this case
D. It recovers both the tables but the names would be changed to the ones assigned in the RECYCLEBIN
Answer» C. It does not recover any of the tables because FLASHBACK is not possible in this case
3.

What would be the outcome of the below query?

A. It would not display any values
B. It would display the value TWO once
C. It would display the value TWO twice
D. It would display the values ONE, TWO, and TWO
Answer» D. It would display the values ONE, TWO, and TWO
4.

Which is the process of breaking a relation into multiple relations:

A. Functional dependency
B. Database modeling
C. Normalization
D. Decomposition
Answer» E.
5.

EMPDET is an external table containing the columns EMPNO and ENAME. Which command would work in relation to the EMPDET table?

A. UPDATE empdetSET ename = 'Amit'WHERE empno = 1234;
B. DELETE FROM empdetWHERE ename LIKE 'J%';
C. CREATE VIEW empvuASSELECT * FROM empdept;
D. CREATE INDEXempdet_idxON empdet(empno);
Answer» D. CREATE INDEXempdet_idxON empdet(empno);
6.

In which scenario would you use the ROLLUP operator for expression or columns within a GROUP BY clause?

A. To find the groups forming the subtotal in a row
B. To create group-wise grand totals for the groups specified within a GROUP BY clause
C. To create a grouping for expressions or columns specified within a GROUP BY clause in one direction, from right to left for calculating the subtotals
D. To create a grouping for expressions or columns specified within a GROUP BY clause in all possible directions, which is cross-tabular report for calculating the subtotals
Answer» D. To create a grouping for expressions or columns specified within a GROUP BY clause in all possible directions, which is cross-tabular report for calculating the subtotals
7.

A non-correlated subquery can be defined as ______

A. A set of sequential queries, all of which must always return a single value
B. A set of sequential queries, all of which must return values from the same table
C. A SELECT statement that can be embedded in a clause of another SELECT statement only
D. A set of one or more sequential queries in which generally the result of the inner query is used as the search value in the outer query
Answer» E.
8.

_______________ joins are SQL server default

A. Outer
B. Inner
C. Equi
D. None of the Mentioned
Answer» C. Equi
9.

Which is refers to a stalemate situation due to which no further progress is possible as computer await response of each other:

A. Concurrency
B. Deadlock
C. Backup
D. Recovery
Answer» C. Backup
10.

Which of the following are functions of Database Manager ?1. Interacting with File Manager2. Creating Queries to Access data3. Security Enforcement4. Database Definition and Schema Generation

A. 1 and 2
B. 3 and 1
C. 1, 2 and 3
D. All of these
Answer» D. All of these
11.

Selecting the victim to be rollbacked to the previous state is determined by the minimum cost. The factors determining cost of rollback is

A. How long the transaction has computed, and how much longer the transaction will compute before it completes its designated task.
B. How many data items the transaction has used.
C. How many more data items the transaction needs for it to complete and how many transactions will be involved in the rollback.
D. All of the above
Answer» E.
12.

Which of these is data type long literal?

A. 0x99fffL
B. ABCDEFG
C. 0x99fffa
D. 99671246
Answer» B. ABCDEFG
13.

Which is essential a business problem not a data problem:

A. Data
B. Database
C. Database design
D. All of the mentioned
Answer» D. All of the mentioned
14.

__________ rollback requires the system to maintain additional information about the state of all the running transactions.

A. Total
B. Partial
C. Time
D. Commit
Answer» C. Time
15.

__________ are used to ensure that transactions access each data item in order of the transactions’ ____ if their accesses conflict.

A. Zone
B. Relay
C. Line
D. Timestamps
Answer» E.
16.

How many types of recovery control techniques:

A. 2
B. 3
C. 4
D. 5
Answer» B. 3
17.

Who detects the failure of the system and restore the database to consistent state ?

A. Database Administrator
B. Application Programmer
C. Naive User
D. Storage Manager
Answer» E.
18.

Which server can joins the indexes when only multiple indexes combined can cover the query:

A. SQL
B. DBMS
C. RDBMS
D. All of the mentioned
Answer» B. DBMS
19.

A deadlock exists in the system if and only if the wait-for graph contains a ___________.

A. Cycle
B. Direction
C. Bi-direction
D. Rotation
Answer» B. Direction
20.

In concurrency control policy the the lock is obtained on

A. Entire database
B. A particular transaction alone
C. All the new elements
D. All of the mentioned
Answer» B. A particular transaction alone
21.

Which formal method that locates and analyses relation schemas on the basis of their primary, candidate keys, and the FD’s that are present among the attributes of these schemas:

A. Functional dependency
B. Database modeling
C. Normalization
D. Decomposition
Answer» D. Decomposition
22.

Some of the utilities of DBMS are _____________i) Loading ii) Backup iii) File organization iv) Process Organization

A. i, ii, and iv only
B. i, ii and iii only
C. ii, iii and iv only
D. All i, ii, iii, and iv
Answer» C. ii, iii and iv only
23.

______________ requires that data should be made available to only authorized users.

A. Data integrity
B. Privacy
C. Security
D. None of the Mentioned
Answer» D. None of the Mentioned
24.

____________ is an interface between low level database and application program.

A. Database Associator
B. Database Server
C. Database Manage
D. None of these
Answer» D. None of these
25.

Which of the following is not a state in transaction ?

A. Active
B. Terminated
C. Aborted
D. Partially committed
Answer» C. Aborted
26.

A concurrency-control policy such as this one leads to ______ performance, since it forces transactions to wait for preceding transactions to finish before they can start.

A. Good
B. Average
C. Poor
D. Unstable
Answer» D. Unstable
27.

____________ allows individual row operation to be performed on a given result set or on the generated by a selected by a selected statement.

A. Procedure
B. Trigger
C. Curser
D. None of the Mentioned
Answer» D. None of the Mentioned
28.

Which are types of recovery control techniques:

A. Deferred update
B. Immediate update
C. All of the Mentioned
D. None of the Mentioned
Answer» D. None of the Mentioned
29.

Transaction processing is associated with everything below except

A. producing detail, summary, or exception reports
B. recording a business activity
C. confirming an action or triggering a response
D. maintaining data
Answer» D. maintaining data
30.

Which of the following is not a property of transactions?

A. Atomicity
B. Concurrency
C. Isolation
D. Durability
Answer» E.
31.

The deadlock in a set of transaction can be determined by

A. Read-only graph
B. Wait graph
C. Wait-for graph
D. All of the mentioned
Answer» B. Wait graph
32.

The SQL statement SELECT SUBSTR(‘123456789’, INSTR(‘abcabcabc’,’b’), 4) FROM EMP; prints

A. 6789
B. 2345
C. 1234
D. 456789
Answer» C. 1234
33.

_______________ provides option for entering SQL queries as execution time, rather than at the development stage.

A. PL/SQL
B. SQL*Plus
C. SQL
D. Dynamic SQL
Answer» E.
34.

When SQL statements are embedded inside 3GL, we call such a program as

A. Nested query
B. Nested programming
C. Distinct query
D. Embedded SQL
Answer» E.
35.

What is the disadvantage of locking?

A. Does not control concurrency
B. Is not atomic
C. Is not durable
D. Has a poor degree of concurrency
Answer» E.
36.

____ means that the data used during the execution of a transaction cannot be used by a second transaction until the first one is completed.

A. Consistency
B. Atomicity
C. Durability
D. Isolation
Answer» E.
37.

Consider money is transferred from (1)account-A to account-B and (2) account-B to account-A. Which of the following form a transaction ?

A. Only 1
B. Only 2
C. Both 1 and 2 individually
D. Either 1 or 2
Answer» D. Either 1 or 2
38.

Which of the following has “all-or-none” property ?

A. Atomicity
B. Durability
C. Isolation
D. All of the mentioned
Answer» B. Durability
39.

The property of transaction that persists all the crashes is

A. Atomicity
B. Durability
C. Isolation
D. All of the mentioned
Answer» C. Isolation
40.

The Oracle RDBMS uses the ____ statement to declare a new transaction start and its properties.

A. BEGIN
B. SET TRANSACTION
C. BEGIN TRANSACTION
D. COMMIT
Answer» C. BEGIN TRANSACTION
41.

Which of the following is not a type of a schedule?

A. Partial schedule
B. Dependent schedule
C. Recoverable schedule
D. None of the mentioned
Answer» E.
42.

If a schedule is equivalent to a serial schedule, it is called as a _________

A. Serializable schedule
B. Equivalent schedule
C. Committed schedule
D. None of the mentioned
Answer» B. Equivalent schedule
43.

Which of the following is a transaction isolation level as specified by SQL standard?

A. Serializable
B. Repeatable read
C. Read committed
D. All of the mentioned
Answer» B. Repeatable read
44.

The application of database management system in air flight seat booking in a way that one seat is accessed by only one clerk for customer reservation is classified as

A. online transaction processing
B. offline transaction processing
C. online logical representation
D. offline modeling representation
Answer» B. offline transaction processing
45.

The “all-or-none” property is commonly referred to as _________

A. Isolation
B. Durability
C. Atomicity
D. None of the mentioned
Answer» D. None of the mentioned
46.

Transaction management ensures ____________ and __________ properties.

A. Atomicity and Intigrity
B. Atomicity and Durability
C. Atomicity and Abstraction
D. None of these
Answer» C. Atomicity and Abstraction
47.

Which statement is true regarding external tables?

A. The default REJECT LIMIT for external tables is UNLIMITED
B. The data and metadata for an external table are stored outside the database
C. ORACLE_LOADER and ORACLE_DATAPUMP have exactly the same functionality when used with an external table
D. The CREATE TABLE AS SELECT statement can be used to unload data into regular table in the database from an external table
Answer» E.
48.

In database management system, the executing process or executing program which considers the updating or reading of records stored in database is called

A. conceptualization
B. execution
C. implementation
D. transaction
Answer» E.
49.

In ___________ isolation each transaction is given its own version of the database

A. Timestamp
B. Snapshot
C. Lock based
D. All of the mentioned
Answer» C. Lock based
50.

SNAPSHOT is used for (DBA)

A. Synonym
B. Tablespace
C. System server
D. Dynamic data replication
Answer» E.