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Browse exam-wise, subject-wise, and country-wise MCQs with explanations.
Choose an option to check your answer.
A.
a graph used to encrypt user passwords
B.
a graph used to test conflict serializability by checking cycles
C.
a MongoDB replication topology only
D.
a diagram used only for ER modeling
Show Answer
Correct Answer: B. a graph used to test conflict serializability by checking cycles
Explanation:
This statement is correct because precedence graph means that a graph used to test conflict serializability by checking cycles.
Choose an option to check your answer.
A.
a graph used to encrypt user passwords
B.
a graph used to test conflict serializability by checking cycles
C.
a MongoDB replication topology only
D.
a diagram used only for ER modeling
Show Answer
Correct Answer: B. a graph used to test conflict serializability by checking cycles
Explanation:
precedence graph is used in Advanced DBMS because a graph used to test conflict serializability by checking cycles.
Choose an option to check your answer.
A.
a graph used to test conflict serializability by checking cycles
B.
a graph used to encrypt user passwords
C.
a diagram used only for ER modeling
D.
a MongoDB replication topology only
Show Answer
Correct Answer: A. a graph used to test conflict serializability by checking cycles
Explanation:
The correct answer explains precedence graph in the context of Transactions.
Choose an option to check your answer.
A.
all schedules with deadlocks are accepted
B.
transactions are serializable only when they use NoSQL
C.
queries are optimized by removing predicates
D.
a schedule can be transformed to a serial schedule by swapping non-conflicting operations
Show Answer
Correct Answer: D. a schedule can be transformed to a serial schedule by swapping non-conflicting operations
Explanation:
This statement is correct because conflict serializability means that a schedule can be transformed to a serial schedule by swapping non-conflicting operations.
Choose an option to check your answer.
A.
all schedules with deadlocks are accepted
B.
queries are optimized by removing predicates
C.
transactions are serializable only when they use NoSQL
D.
a schedule can be transformed to a serial schedule by swapping non-conflicting operations
Show Answer
Correct Answer: D. a schedule can be transformed to a serial schedule by swapping non-conflicting operations
Explanation:
conflict serializability is used in Advanced DBMS because a schedule can be transformed to a serial schedule by swapping non-conflicting operations.
Choose an option to check your answer.
A.
transactions are serializable only when they use NoSQL
B.
queries are optimized by removing predicates
C.
all schedules with deadlocks are accepted
D.
a schedule can be transformed to a serial schedule by swapping non-conflicting operations
Show Answer
Correct Answer: D. a schedule can be transformed to a serial schedule by swapping non-conflicting operations
Explanation:
The correct answer explains conflict serializability in the context of Transactions.
Choose an option to check your answer.
A.
a schedule that stores records in serial files only
B.
an interleaved schedule produces the same effect as some serial schedule
C.
a schedule with no transaction commits
D.
a schedule that ignores isolation
Show Answer
Correct Answer: B. an interleaved schedule produces the same effect as some serial schedule
Explanation:
This statement is correct because serializable schedule means that an interleaved schedule produces the same effect as some serial schedule.
Choose an option to check your answer.
A.
a schedule that ignores isolation
B.
an interleaved schedule produces the same effect as some serial schedule
C.
a schedule that stores records in serial files only
D.
a schedule with no transaction commits
Show Answer
Correct Answer: B. an interleaved schedule produces the same effect as some serial schedule
Explanation:
serializable schedule is used in Advanced DBMS because an interleaved schedule produces the same effect as some serial schedule.
Choose an option to check your answer.
A.
a schedule that ignores isolation
B.
a schedule that stores records in serial files only
C.
an interleaved schedule produces the same effect as some serial schedule
D.
a schedule with no transaction commits
Show Answer
Correct Answer: C. an interleaved schedule produces the same effect as some serial schedule
Explanation:
The correct answer explains serializable schedule in the context of Transactions.
Choose an option to check your answer.
A.
transactions execute only on multiple distributed sites
B.
every query is optimized using only sorting
C.
transactions execute one after another without interleaving operations
D.
all locks are released before reading
Show Answer
Correct Answer: C. transactions execute one after another without interleaving operations
Explanation:
This statement is correct because serial schedule means that transactions execute one after another without interleaving operations.
Choose an option to check your answer.
A.
all locks are released before reading
B.
transactions execute only on multiple distributed sites
C.
every query is optimized using only sorting
D.
transactions execute one after another without interleaving operations
Show Answer
Correct Answer: D. transactions execute one after another without interleaving operations
Explanation:
serial schedule is used in Advanced DBMS because transactions execute one after another without interleaving operations.
Choose an option to check your answer.
A.
transactions execute only on multiple distributed sites
B.
transactions execute one after another without interleaving operations
C.
all locks are released before reading
D.
every query is optimized using only sorting
Show Answer
Correct Answer: B. transactions execute one after another without interleaving operations
Explanation:
The correct answer explains serial schedule in the context of Transactions.
