37 + Interview Questions in Transactions in Rdbms Page 1 InterviewSolution

1.	In ___________ isolation each transaction is given its own version of the database(a) Timestamp(b) Snapshot(c) Lock based(d) All of the mentionedI had been asked this question by my school teacher while I was bunking the class.This intriguing question originated from Transaction Isolation Levels in division Transactions of RDBMS
Answer» Right ANSWER is (b) SNAPSHOT For explanation: In snapshot isolation, each transaction is GIVEN its own VERSION or snapshot of the DATABASE on which it can operate.

Discussion

2.	When is a timestamp allotted(a) When execution begins(b) When execution is taking place(c) When execution is completed(d) None of the mentionedThis question was posed to me in an online interview.I would like to ask this question from Transaction Isolation Levels topic in division Transactions of RDBMS
Answer» RIGHT ANSWER is (a) When EXECUTION begins The BEST I can explain: Timestamp is allotted when execution of a TRANSACTION begins.

Discussion

3.	State true or false: All the isolation levels disallow dirty writes(a) True(b) FalseThis question was posed to me by my school teacher while I was bunking the class.I want to ask this question from Transaction Isolation Levels in division Transactions of RDBMS
Answer» The correct choice is (a) True For explanation I would say: All the isolation levels above additionally disallow dirty WRITES, that is, they Disallow writes to a data item that has already been WRITTEN by ANOTHER transaction that has not yet committed or ABORTED.

Discussion

4.	___________ allows uncommitted data to be read(a) Read uncommitted(b) Serializable(c) Repeatable read(d) Read committedThis question was posed to me by my college professor while I was bunking the class.Origin of the question is Transaction Isolation Levels in chapter Transactions of RDBMS
Answer» The correct option is (a) Read UNCOMMITTED Explanation: Real uncommitted allows uncommitted DATA to be read. It is the LOWEST isolation LEVEL allowed by SQL.

Discussion

5.	________ allows only committed data to be read, but does not require repeatable reads(a) Read uncommitted(b) Serializable(c) Repeatable read(d) Read committedI had been asked this question during an interview.My question is from Transaction Isolation Levels in division Transactions of RDBMS
Answer» RIGHT answer is (d) READ committed The EXPLANATION: Read committed allows only committed data to be read, but does not REQUIRE repeatable reads. For instance, between TWO reads of a data item by the transaction, another transaction may have updated the data item and committed.

Discussion

6.	________ allows only committed data to be read and further requires that no other transaction is allowed to update it between two reads of a data item by a transaction.(a) Read uncommitted(b) Serializable(c) Repeatable read(d) Read committedI had been asked this question during an online interview.I would like to ask this question from Transaction Isolation Levels in section Transactions of RDBMS
Answer» Correct option is (c) REPEATABLE read Easy explanation: Repeatable read allows only committed data to be read and further requires that no other transaction is allowed to update it between TWO reads of a data item by a transaction. HOWEVER, the transaction may not be serializable with respect to other TRANSACTIONS.

Discussion

7.	State true or false: Serializable level may allow both serializable and non-serializable executions(a) True(b) FalseI had been asked this question in quiz.I need to ask this question from Transaction Isolation Levels in section Transactions of RDBMS
Answer» The correct ANSWER is (a) True To elaborate: SERIALIZABLE level generally allows only serializable executions but in some special CASES, it MAY also ALLOW non-serializable execution.

Discussion

8.	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 mentionedThe question was posed to me in an interview.The query is from Transaction Isolation Levels topic in chapter Transactions of RDBMS
Answer» Right choice is (a) Serializable To explain I WOULD say: Serializable, repeatable read, read COMMITTED and read UNCOMMITTED are the four LEVELS of TRANSACTIONS.

Discussion

9.	Which of the following is not a type of a schedule?(a) Partial schedule(b) Dependent schedule(c) Recoverable schedule(d) None of the mentionedI got this question by my school principal while I was bunking the class.I'm obligated to ask this question of Transaction Isolation topic in division Transactions of RDBMS
Answer» The CORRECT answer is (d) None of the MENTIONED To elaborate: All of the mentioned SCHEDULES i.e. partial schedule, DEPENDENT schedule, recoverable schedule are different types of schedules.

Discussion

10.	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 mentionedI have been asked this question during an online interview.My question is based upon Transaction Isolation in portion Transactions of RDBMS
Answer» The correct ANSWER is (a) Serializable SCHEDULE Easy explanation: If a schedule is EQUIVALENT to a serial schedule, it is CALLED as a Serializable schedule.

Discussion

11.	The average time for a transaction to be completed after it has been submitted is called as __________(a) Minimum response time(b) Average response time(c) Average reaction time(d) Minimum reaction timeI had been asked this question by my college director while I was bunking the class.My doubt is from Transaction Isolation in chapter Transactions of RDBMS
Answer» The correct option is (b) Average response TIME Explanation: The average time for a transaction to be completed after it has been submitted is CALLED as Average response time. This gets decreased when CONCURRENCY is USED in transactions.

Discussion

12.	Which of the following are the advantages of transaction concurrency?(a) Increased throughput(b) Increased utilization(c) Reduces average response time(d) All of the mentionedThis question was posed to me in class test.This key question is from Transaction Isolation in section Transactions of RDBMS
Answer» Right answer is (d) All of the mentioned The explanation: Concurrency in TRANSACTIONS ALLOW increased throughput, utilization. They also reduce average RESPONSE TIME.

Discussion

13.	State true or false: Transactions can only run serially(a) True(b) FalseI had been asked this question at a job interview.Origin of the question is Transaction Isolation topic in section Transactions of RDBMS
Answer» The CORRECT choice is (B) False The BEST I can explain: Transactions are SAFER run serially but can also be run concurrently.

Discussion

14.	A ___________ is one where, for each pair of transactions Ti and Tj such that Tj reads a data item previously written by Ti , the commit operation of Ti appears before the commit operation of Tj(a) Partial schedule(b) Dependent schedule(c) Recoverable schedule(d) None of the mentionedThe question was asked in an online quiz.I would like to ask this question from Transaction Isolation in chapter Transactions of RDBMS
Answer» Correct option is (c) RECOVERABLE schedule Explanation: A Recoverable schedule is one where, for each PAIR of transactions TI and Tj such that Tj reads a data item PREVIOUSLY written by Ti , the COMMIT operation of Ti appears before the commit operation of Tj.

Discussion

15.	State true or false: Every cascadeless schedule is also recoverable(a) True(b) FalseI have been asked this question during an interview.I would like to ask this question from Transaction Isolation in section Transactions of RDBMS
Answer» Right answer is (a) True Explanation: EVERY cascadeless schedule is also recoverable because in a cascadeless schedule, the COMMIT operations occur in the same SEQUENCE as that of WRITE and read operations of two TRANSACTIONS respectively.

Discussion

16.	The phenomenon in which one failure leads to a series of transaction rollbacks is called as ________(a) Cascading rollback(b) Cascadeless rollback(c) Cascade cause(d) None of the mentionedThe question was posed to me in an online interview.The question is from Transaction Isolation in section Transactions of RDBMS
Answer» The correct option is (a) Cascading rollback Explanation: The PHENOMENON in which one failure leads to a series of transaction rollbacks is called as cascading rollback. B=It is named so because one failure CAUSES the rollback of several other TRANSACTIONS SERIALLY.

Discussion

17.	A transaction that performs only one operation is called as a _________(a) Partial schedule(b) Complete schedule(c) Dependent schedule(d) Independent scheduleThis question was posed to me in unit test.I want to ask this question from Transaction Isolation in chapter Transactions of RDBMS
Answer» Right answer is (a) PARTIAL schedule To ELABORATE: A transaction that performs only ONE OPERATION is called as a partial schedule because we don’t include commit or ROLLBACK operations on them.

Discussion

18.	Which of the following is the most expensive method?(a) Timestamping(b) Plain locking(c) Predicate locking(d) Snapshot isolationI have been asked this question during an online interview.My doubt stems from Serializability topic in section Transactions of RDBMS
Answer» The correct OPTION is (c) Predicate locking For EXPLANATION: Predicate locking is the most EXPENSIVE method and is generally not used in most databases.

Discussion

19.	State true or false: If I = read(Q) and J = write(Q) then the order of I and J does not matter.(a) True(b) FalseThis question was addressed to me in final exam.This question is from Serializability topic in division Transactions of RDBMS
Answer» The CORRECT OPTION is (b) False Easiest explanation: If I = read(Q) and J = write(Q) then the order of I and J MATTERS because both Iand J are different operations on the query. The order of execution determines the state of the DATABASE that is being read or written.

Discussion

20.	State true or false: If I = read(Q) and J = read(Q) then the order of I and J does not matter.(a) True(b) FalseThe question was asked by my school principal while I was bunking the class.Query is from Serializability topic in division Transactions of RDBMS
Answer» CORRECT choice is (a) True Explanation: If I = read(Q) and J = read(Q) then the ORDER of I and J does not matter because both Iand J are read OPERATIONS on the query.

Discussion

21.	A ___________of the transactions can be obtained by finding a linear order consistent with the partial order of the precedence graph.(a) Serializability order(b) Direction graph(c) Precedence graph(d) Scheduling schemeI had been asked this question in exam.My question is from Serializability topic in section Transactions of RDBMS
Answer» The correct option is (a) Serializability order For explanation I would SAY: A Serializability order of the transactions can be obtained by finding a LINEAR order CONSISTENT with the partial order of the precedence graph. This process is called as topological sorting.

Discussion

22.	The set of ________ in a precedence graph consists of all the transactions participating in the schedule(a) Vertices(b) Edges(c) Directions(d) None of the mentionedThis question was addressed to me in an international level competition.Question is from Serializability in portion Transactions of RDBMS
Answer» CORRECT choice is (a) VERTICES Explanation: The set of vertices in a precedence graph consists of all the transactions PARTICIPATING in the schedule. Precedence graph is a simple and efficient way of determining CONFLICT serializability of the schedule.

Discussion

23.	A schedule is __________ if it is conflict equivalent to a serial schedule.(a) Conflict serializable(b) Conflicting(c) Non serializable(d) None of the mentionedI got this question in final exam.This intriguing question originated from Serializability topic in chapter Transactions of RDBMS
Answer» The correct option is (a) Conflict SERIALIZABLE Easy EXPLANATION: A schedule is conflict serializable if it is conflict equivalent to a serial schedule. The CONCEPT of conflict equivalence leads to the concept.

Discussion

24.	If a schedule S can be transformed into a schedule S’ by a series of swaps of non-conflicting instructions, then S and S’ are(a) Non conflict equivalent(b) Equal(c) Conflict equivalent(d) Isolation equivalentThis question was addressed to me during an interview.This key question is from Serializability topic in division Transactions of RDBMS
Answer» Right option is (c) Conflict EQUIVALENT The best I can EXPLAIN: If a schedule S can be TRANSFORMED into a schedule S’ by a series of swaps of non-conflicting instructions, then S and S’ are conflict equivalent. Not all serial SCHEDULES are conflict equivalent to each other.

Discussion

25.	I and J are _________ if they are operations by different transactions on the same data item, and at least one of them is a write operation.(a) Conflicting(b) Overwriting(c) Isolated(d) DurableI had been asked this question during an interview.Question is taken from Serializability topic in portion Transactions of RDBMS
Answer» Right OPTION is (a) Conflicting Explanation: I and J are conflicting if they are operations by DIFFERENT transactions on the same DATA item, and at least one of them is a WRITE OPERATION.

Discussion

26.	The scheme that controls the interaction between executing transactions is called as _____(a) Concurrency control scheme(b) Multiprogramming scheme(c) Serialization scheme(d) Schedule schemeThe question was asked by my college professor while I was bunking the class.My query is from Transaction Concept and Model in division Transactions of RDBMS
Answer» CORRECT choice is (a) Concurrency control SCHEME Explanation: The scheme that CONTROLS the interaction between executing TRANSACTIONS is called as concurrency control scheme.

Discussion

27.	The execution sequences in concurrency control are termed as ________(a) Serials(b) Schedules(c) Organizations(d) Time tablesI had been asked this question in final exam.This is a very interesting question from Transaction Concept and Model topic in portion Transactions of RDBMS
Answer» Right answer is (B) SCHEDULES Easy explanation: The execution sequences in concurrency control are KNOWN as schedules.

Discussion

28.	Which of the following is not a transaction state?(a) Active(b) Partially committed(c) Failed(d) CompensatedI have been asked this question by my school teacher while I was bunking the class.The query is from Transaction Concept and Model in chapter Transactions of RDBMS
Answer» The correct option is (d) COMPENSATED To explain: Compensated is not a TRANSACTION state. But ACTIVE, partially committed and failed are DIFFERENT states of a transaction.

Discussion

29.	A transaction that has not been completed successfully is called as _______(a) Compensating transaction(b) Aborted transaction(c) Active transaction(d) Partially committed transactionThe question was asked in my homework.My doubt stems from Transaction Concept and Model in chapter Transactions of RDBMS
Answer» CORRECT OPTION is (b) ABORTED transaction For explanation I would say: Aborted transaction is a state after the transaction has been rolled back and the DATABASE has been RESTORED to the state prior to the transaction.

Discussion

30.	State true or false: Information residing in the volatile storage does not usually survive system crashes(a) True(b) FalseThe question was asked during an interview for a job.The doubt is from Transaction Concept and Model topic in portion Transactions of RDBMS
Answer» The correct option is (a) True Best explanation: INFORMATION RESIDING in the volatile STORAGE does not USUALLY survive system crashes but the information in stable storage can survive system crashes EFFICIENTLY.

Discussion

31.	Which of the following systems is responsible for ensuring isolation?(a) Recovery system(b) Atomic system(c) Concurrency control system(d) Compiler systemThis question was addressed to me in an interview for internship.This intriguing question originated from Transaction Concept and Model topic in portion Transactions of RDBMS
Answer» Right choice is (C) Concurrency control system The best EXPLANATION: The concurrency control system is RESPONSIBLE for ensuring isolation in a database system.

Discussion

32.	Which of the following systems is responsible for ensuring durability?(a) Recovery system(b) Atomic system(c) Concurrency control system(d) Compiler systemI had been asked this question in an international level competition.I'm obligated to ask this question of Transaction Concept and Model topic in section Transactions of RDBMS
Answer» Right answer is (a) RECOVERY system The best explanation: The recovery system is responsible for the maintenance of DURABILITY. In ADDITION, it also ensures ATOMICITY.

Discussion

33.	Which of the following is not a property of a transaction?(a) Atomicity(b) Simplicity(c) Isolation(d) DurabilityI got this question in my homework.My enquiry is from Transaction Concept and Model topic in portion Transactions of RDBMS
Answer» The correct ANSWER is (b) Simplicity For explanation: Simplicity is not a PROPERTY of a transaction. ATOMICITY, Isolation, Durability are all PARTS of ACID properties.

Discussion

34.	Execution of translation in isolation preserves the _________ of a database(a) Atomicity(b) Consistency(c) Durability(d) All of the mentionedI had been asked this question in examination.This question is from Transaction Concept and Model topic in division Transactions of RDBMS
Answer» The correct option is (b) Consistency The BEST I can explain: Execution of TRANSLATION in isolation PRESERVES the consistency of a database. It ensures that no other TRANSACTION is running concurrently.

Discussion

35.	Which of the following is a property of transactions?(a) Atomicity(b) Durability(c) Isolation(d) All of the mentionedI got this question during an internship interview.I'm obligated to ask this question of Transaction Concept and Model in portion Transactions of RDBMS
Answer» Correct option is (d) All of the mentioned Easiest explanation: Atomicity, Durability and ISOLATION are all PROPERTIES of TRANSACTIONS.

Discussion

36.	The “all-or-none” property is commonly referred to as _________(a) Isolation(b) Durability(c) Atomicity(d) None of the mentionedI got this question in my homework.I want to ask this question from Transaction Concept and Model topic in section Transactions of RDBMS
Answer» The CORRECT option is (C) Atomicity To ELABORATE: The all or none policy is commonly referred to as atomicity. It ENSURES that a work is either completed or not completed and there are no intermediate STAGES.

Discussion

37.	Collections of operations that form a single logical unit of work are called __________(a) Views(b) Networks(c) Units(d) TransactionsI got this question during an interview.The above asked question is from Transaction Concept and Model topic in portion Transactions of RDBMS
Answer» The correct OPTION is (d) Transactions Explanation: Collections of operations that form a single logical unit of WORK are CALLED transactions. A database system must ensure proper EXECUTION of transactions.

Discussion

Explore topic-wise InterviewSolutions in .

State true or false: All the isolation levels disallow dirty writes(a) True(b) FalseThis question was posed to me by my school teacher while I was bunking the class.I want to ask this question from Transaction Isolation Levels in division Transactions of RDBMS

___________ allows uncommitted data to be read(a) Read uncommitted(b) Serializable(c) Repeatable read(d) Read committedThis question was posed to me by my college professor while I was bunking the class.Origin of the question is Transaction Isolation Levels in chapter Transactions of RDBMS

________ allows only committed data to be read, but does not require repeatable reads(a) Read uncommitted(b) Serializable(c) Repeatable read(d) Read committedI had been asked this question during an interview.My question is from Transaction Isolation Levels in division Transactions of RDBMS

State true or false: Serializable level may allow both serializable and non-serializable executions(a) True(b) FalseI had been asked this question in quiz.I need to ask this question from Transaction Isolation Levels in section Transactions of RDBMS

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 mentionedThe question was posed to me in an interview.The query is from Transaction Isolation Levels topic in chapter Transactions of RDBMS

Which of the following are the advantages of transaction concurrency?(a) Increased throughput(b) Increased utilization(c) Reduces average response time(d) All of the mentionedThis question was posed to me in class test.This key question is from Transaction Isolation in section Transactions of RDBMS

State true or false: Transactions can only run serially(a) True(b) FalseI had been asked this question at a job interview.Origin of the question is Transaction Isolation topic in section Transactions of RDBMS

State true or false: Every cascadeless schedule is also recoverable(a) True(b) FalseI have been asked this question during an interview.I would like to ask this question from Transaction Isolation in section Transactions of RDBMS

A transaction that performs only one operation is called as a _________(a) Partial schedule(b) Complete schedule(c) Dependent schedule(d) Independent scheduleThis question was posed to me in unit test.I want to ask this question from Transaction Isolation in chapter Transactions of RDBMS

Which of the following is the most expensive method?(a) Timestamping(b) Plain locking(c) Predicate locking(d) Snapshot isolationI have been asked this question during an online interview.My doubt stems from Serializability topic in section Transactions of RDBMS

State true or false: If I = read(Q) and J = write(Q) then the order of I and J does not matter.(a) True(b) FalseThis question was addressed to me in final exam.This question is from Serializability topic in division Transactions of RDBMS

State true or false: If I = read(Q) and J = read(Q) then the order of I and J does not matter.(a) True(b) FalseThe question was asked by my school principal while I was bunking the class.Query is from Serializability topic in division Transactions of RDBMS

A schedule is __________ if it is conflict equivalent to a serial schedule.(a) Conflict serializable(b) Conflicting(c) Non serializable(d) None of the mentionedI got this question in final exam.This intriguing question originated from Serializability topic in chapter Transactions of RDBMS

The execution sequences in concurrency control are termed as ________(a) Serials(b) Schedules(c) Organizations(d) Time tablesI had been asked this question in final exam.This is a very interesting question from Transaction Concept and Model topic in portion Transactions of RDBMS

Which of the following is not a transaction state?(a) Active(b) Partially committed(c) Failed(d) CompensatedI have been asked this question by my school teacher while I was bunking the class.The query is from Transaction Concept and Model in chapter Transactions of RDBMS

State true or false: Information residing in the volatile storage does not usually survive system crashes(a) True(b) FalseThe question was asked during an interview for a job.The doubt is from Transaction Concept and Model topic in portion Transactions of RDBMS

Which of the following is not a property of a transaction?(a) Atomicity(b) Simplicity(c) Isolation(d) DurabilityI got this question in my homework.My enquiry is from Transaction Concept and Model topic in portion Transactions of RDBMS

Execution of translation in isolation preserves the _________ of a database(a) Atomicity(b) Consistency(c) Durability(d) All of the mentionedI had been asked this question in examination.This question is from Transaction Concept and Model topic in division Transactions of RDBMS

Which of the following is a property of transactions?(a) Atomicity(b) Durability(c) Isolation(d) All of the mentionedI got this question during an internship interview.I'm obligated to ask this question of Transaction Concept and Model in portion Transactions of RDBMS

The “all-or-none” property is commonly referred to as _________(a) Isolation(b) Durability(c) Atomicity(d) None of the mentionedI got this question in my homework.I want to ask this question from Transaction Concept and Model topic in section Transactions of RDBMS

Collections of operations that form a single logical unit of work are called __________(a) Views(b) Networks(c) Units(d) TransactionsI got this question during an interview.The above asked question is from Transaction Concept and Model topic in portion Transactions of RDBMS