What is Lock Based Protocol and what is its use?
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Answer / bhargavi
lock based protocol: Once one transaction is accessing the
data,no other transaction is made to modify the data.
(or)
A locking protocol is a set of rules to be followed by each
transaction to ensure that, even though actions of several
transactions might be interleaved,the net effect is
identical to executing all transactions in some serial order.
Is This Answer Correct ? | 55 Yes | 9 No |
Answer / amit yadav
A lock is a mechanism to control concurrent access to a data
item
Data items can be locked in two modes :
1. exclusive (X) mode. Data item can be both read as well as
written. X-lock is requested using lock-X instruction.
2. shared (S) mode. Data item can only be read. S-lock is
requested using lock-S instruction.
Lock requests are made to concurrency-control manager.
Transaction can
proceed only after request is granted.
Is This Answer Correct ? | 8 Yes | 0 No |
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