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)

Explain trivial dependency, Explain trivial dependency? Functional depe...

Explain trivial dependency? Functional dependency of the form α ->β. is trivial if α C β. Trivial functional dependencies are satisfied by all the relations.

Special comparison operator used in where clause-dml, Special comparison op...

Special comparison operator used in where Clause a.   between. ...and...It gives range among two values (inclusive) Example: SELECT ENAME, SAL FROM EMP WHERE SAL BETWE

DBMS, what is specialization?

what is specialization?

Information infrasctructure., what factors might influence a company to out...

what factors might influence a company to outsource its IT infrascture.

Explain the timestamps for read operations, Timestamps For Read operations:...

Timestamps For Read operations: If TS (T) If TS (T) >= W-timestamp (Q), then the transaction T is trying to read a value of data item Q which has been written and committed

What is online transaction processing, What is OLTP (Online Transaction Pro...

What is OLTP (Online Transaction Processing)? In OLTP - online transaction processing systems relational database design use the discipline of data modeling and generally follo

Briefly describe concurrency execution, Briefly describe concurrency execut...

Briefly describe concurrency execution? Lock - based protocols Locks There are several modes in which a data item may be locked in this section we restrict our attention

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