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Choose an option to check your answer.
A.
a lock that allows all users to update together
B.
a password policy for administrators
C.
a lock only for opening database files
D.
a lock required for writing that prevents other conflicting reads or writes
Show Answer
Correct Answer: D. a lock required for writing that prevents other conflicting reads or writes
Explanation:
This statement is correct because exclusive lock means that a lock required for writing that prevents other conflicting reads or writes.
Choose an option to check your answer.
A.
a lock only for opening database files
B.
a lock required for writing that prevents other conflicting reads or writes
C.
a password policy for administrators
D.
a lock that allows all users to update together
Show Answer
Correct Answer: B. a lock required for writing that prevents other conflicting reads or writes
Explanation:
exclusive lock is used in Advanced DBMS because a lock required for writing that prevents other conflicting reads or writes.
Choose an option to check your answer.
A.
a lock that allows all users to update together
B.
a lock required for writing that prevents other conflicting reads or writes
C.
a password policy for administrators
D.
a lock only for opening database files
Show Answer
Correct Answer: B. a lock required for writing that prevents other conflicting reads or writes
Explanation:
The correct answer explains exclusive lock in the context of Concurrency Control.
Choose an option to check your answer.
A.
a lock that permits every update operation
B.
a lock that allows concurrent reading but prevents conflicting writes
C.
a lock that permanently disables a user account
D.
a lock used only for deleting files
Show Answer
Correct Answer: B. a lock that allows concurrent reading but prevents conflicting writes
Explanation:
This statement is correct because shared lock means that a lock that allows concurrent reading but prevents conflicting writes.
Choose an option to check your answer.
A.
a lock that permanently disables a user account
B.
a lock that permits every update operation
C.
a lock that allows concurrent reading but prevents conflicting writes
D.
a lock used only for deleting files
Show Answer
Correct Answer: C. a lock that allows concurrent reading but prevents conflicting writes
Explanation:
shared lock is used in Advanced DBMS because a lock that allows concurrent reading but prevents conflicting writes.
Choose an option to check your answer.
A.
a lock used only for deleting files
B.
a lock that permits every update operation
C.
a lock that permanently disables a user account
D.
a lock that allows concurrent reading but prevents conflicting writes
Show Answer
Correct Answer: D. a lock that allows concurrent reading but prevents conflicting writes
Explanation:
The correct answer explains shared lock in the context of Concurrency Control.
Choose an option to check your answer.
A.
deadlocks cannot occur under any condition
B.
all locks are released before the first write
C.
exclusive locks are held until the transaction commits or aborts
D.
shared locks are never used
Show Answer
Correct Answer: C. exclusive locks are held until the transaction commits or aborts
Explanation:
This statement is correct because strict two-phase locking means that exclusive locks are held until the transaction commits or aborts.
Choose an option to check your answer.
A.
all locks are released before the first write
B.
deadlocks cannot occur under any condition
C.
shared locks are never used
D.
exclusive locks are held until the transaction commits or aborts
Show Answer
Correct Answer: D. exclusive locks are held until the transaction commits or aborts
Explanation:
strict two-phase locking is used in Advanced DBMS because exclusive locks are held until the transaction commits or aborts.
Choose an option to check your answer.
A.
shared locks are never used
B.
deadlocks cannot occur under any condition
C.
all locks are released before the first write
D.
exclusive locks are held until the transaction commits or aborts
Show Answer
Correct Answer: D. exclusive locks are held until the transaction commits or aborts
Explanation:
The correct answer explains strict two-phase locking in the context of Concurrency Control.
Choose an option to check your answer.
A.
all transactions execute without locks
B.
a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks
C.
locks are acquired and released randomly
D.
locks are used only for backup files
Show Answer
Correct Answer: B. a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks
Explanation:
This statement is correct because two-phase locking means that a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks.
Choose an option to check your answer.
A.
a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks
B.
locks are used only for backup files
C.
all transactions execute without locks
D.
locks are acquired and released randomly
Show Answer
Correct Answer: A. a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks
Explanation:
two-phase locking is used in Advanced DBMS because a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks.
Choose an option to check your answer.
A.
a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks
B.
all transactions execute without locks
C.
locks are used only for backup files
D.
locks are acquired and released randomly
Show Answer
Correct Answer: A. a transaction has a growing phase for acquiring locks and a shrinking phase for releasing locks
Explanation:
The correct answer explains two-phase locking in the context of Concurrency Control.
