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Choose an option to check your answer.
A.
reapplies committed updates during recovery to ensure durability
B.
blocks all future transactions
C.
removes every committed transaction
D.
creates a secondary index
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Correct Answer: A. reapplies committed updates during recovery to ensure durability
Explanation:
This statement is correct because redo operation means that reapplies committed updates during recovery to ensure durability.
Choose an option to check your answer.
A.
creates a secondary index
B.
blocks all future transactions
C.
reapplies committed updates during recovery to ensure durability
D.
removes every committed transaction
Show Answer
Correct Answer: C. reapplies committed updates during recovery to ensure durability
Explanation:
redo operation is used in Advanced DBMS because reapplies committed updates during recovery to ensure durability.
Choose an option to check your answer.
A.
creates a secondary index
B.
reapplies committed updates during recovery to ensure durability
C.
removes every committed transaction
D.
blocks all future transactions
Show Answer
Correct Answer: B. reapplies committed updates during recovery to ensure durability
Explanation:
The correct answer explains redo operation in the context of Recovery.
Choose an option to check your answer.
A.
a type of B-tree split
B.
a MongoDB collection validator only
C.
a recovery point that reduces the amount of log scanning after a crash
D.
a password reset operation
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Correct Answer: C. a recovery point that reduces the amount of log scanning after a crash
Explanation:
This statement is correct because checkpoint means that a recovery point that reduces the amount of log scanning after a crash.
Choose an option to check your answer.
A.
a type of B-tree split
B.
a password reset operation
C.
a recovery point that reduces the amount of log scanning after a crash
D.
a MongoDB collection validator only
Show Answer
Correct Answer: C. a recovery point that reduces the amount of log scanning after a crash
Explanation:
checkpoint is used in Advanced DBMS because a recovery point that reduces the amount of log scanning after a crash.
Choose an option to check your answer.
A.
a password reset operation
B.
a MongoDB collection validator only
C.
a recovery point that reduces the amount of log scanning after a crash
D.
a type of B-tree split
Show Answer
Correct Answer: C. a recovery point that reduces the amount of log scanning after a crash
Explanation:
The correct answer explains checkpoint in the context of Recovery.
Choose an option to check your answer.
A.
data pages are always written before log records
B.
log records are written to stable storage before the corresponding data pages are written
C.
logs are used only for user authentication
D.
logs are deleted before commit
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Correct Answer: B. log records are written to stable storage before the corresponding data pages are written
Explanation:
This statement is correct because write-ahead logging means that log records are written to stable storage before the corresponding data pages are written.
Choose an option to check your answer.
A.
log records are written to stable storage before the corresponding data pages are written
B.
logs are deleted before commit
C.
logs are used only for user authentication
D.
data pages are always written before log records
Show Answer
Correct Answer: A. log records are written to stable storage before the corresponding data pages are written
Explanation:
write-ahead logging is used in Advanced DBMS because log records are written to stable storage before the corresponding data pages are written.
Choose an option to check your answer.
A.
logs are used only for user authentication
B.
log records are written to stable storage before the corresponding data pages are written
C.
logs are deleted before commit
D.
data pages are always written before log records
Show Answer
Correct Answer: B. log records are written to stable storage before the corresponding data pages are written
Explanation:
The correct answer explains write-ahead logging in the context of Recovery.
Choose an option to check your answer.
A.
queries are optimized by guessing randomly
B.
transactions are never checked for conflicts
C.
transactions execute first and are validated before commit
D.
all writes require locks before any read
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Correct Answer: C. transactions execute first and are validated before commit
Explanation:
This statement is correct because optimistic concurrency control means that transactions execute first and are validated before commit.
Choose an option to check your answer.
A.
queries are optimized by guessing randomly
B.
transactions are never checked for conflicts
C.
all writes require locks before any read
D.
transactions execute first and are validated before commit
Show Answer
Correct Answer: D. transactions execute first and are validated before commit
Explanation:
optimistic concurrency control is used in Advanced DBMS because transactions execute first and are validated before commit.
Choose an option to check your answer.
A.
all writes require locks before any read
B.
queries are optimized by guessing randomly
C.
transactions execute first and are validated before commit
D.
transactions are never checked for conflicts
Show Answer
Correct Answer: C. transactions execute first and are validated before commit
Explanation:
The correct answer explains optimistic concurrency control in the context of Concurrency Control.
