COMPUTER APPLICATIONS
DATABASE MANAGEMENT SYSTEMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Data manipulation
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Deadlock
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Database lockout
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Data redundancy
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Detailed explanation-1: -A deadlock occurs when multiple users seeking access to the same set of records lockout each other. As a result, the transactions of all users assume a “wait” state until the locks are removed.
Detailed explanation-2: -Locks block data-access operations. Mutual blocking between transactions results in a deadlock, where execution of these transactions is stalled, and no completion can be reached. Thus deadlocks need to be resolved to complete these transactions’ executions and release related computing resources.
Detailed explanation-3: -Deadlock describes a condition in which two or more threads are blocked (hung) forever because they are waiting for each other. There are many causes of deadlocks. The Thread Analyzer detects deadlocks that are caused by the inappropriate use of mutual exclusion locks.
Detailed explanation-4: -Locks in SQL Server A shared lock is applied during the execution of the select query. A shared lock is the same as update lock but the difference is lock time duration. The shared lock has scope only with the select query.