Strict 2pl-two phase locking (2pl), Database Management System

Assignment Help:

Strict 2PL:Though, this basic 2PL suffers from the trouble that it can result into loss of isolation / atomic property of transaction as theoretically speaking once a lock is released on a data item it can be changed by another transaction before the first transaction aborts or commits.

To leave such a situation we use strict two phase locking. The strict 2PL is graphically depicted in Figure. Though, the basic drawbacks of strict 2PL are that it restricts concurrency as it locks the item afar the time it is required by a transaction.

                                 693_Strict 2PL.png

                                                           Figure: Strict Two Phase Locking

Does the two phase locking solve all the problems of concurrent transactions? No, the strict 2PL answers the problem of concurrency and atomicity, though it introduces another problem.


Related Discussions:- Strict 2pl-two phase locking (2pl)

Describe sequential file organization, Describe sequential file organizatio...

Describe sequential file organization.  Explain the rules for (i)  Inserting a new record. (ii)  Deleting an existing record.          Ans:A sequential f

Entity Relationship for music band managem modeliing, i am required to come...

i am required to come up with entities relationships, optionality and cardinality from a scenario. there is a night club and bookings for a musician band

Method of analyzing association traversal, Analyzing Association Traversal ...

Analyzing Association Traversal Till now, we have supposed that associations are bi-directional. But in the case of traversal, it is in only one direction in any application,

What is the error handling, What is the error handling Traditionally, b...

What is the error handling Traditionally, bits have been sent over line lacking any error correcting scheme in physical layer. The presence of the CPU in each modem makes it po

Unrepeatable reads-problems of concurrent transactions, Unrepeatable reads ...

Unrepeatable reads : Assume T7 reads X twice during its implementation. If it did not update X itself it could be very disturbing to see a dissimilar value of X in its next read. B

Define partial, Partial Key : It is a group of attributes that can uniquel...

Partial Key : It is a group of attributes that can uniquely identify small entities and that are related to same base entity. It is sometime named as Discriminator.  Altern

Define two phase commit, Define Two phase commit Two phase commit: To m...

Define Two phase commit Two phase commit: To make sure atomicity, all the sites where a transaction is being executed must agree on the final outcome of the execution. The tran

Oracle, how oracle can be used

how oracle can be used

Objectives-file organisation in dbms, Objectives  After reading this un...

Objectives  After reading this unit you should be able to: Explain storage of databases on hard disks; Discuss the execution of various file Organisation techniques;

Update operations, The Update Operations : Update operations are used fo...

The Update Operations : Update operations are used for altering database values. The constraint violations faced by this operation are logically the similar as the problem faced

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd