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)

Define boyce codd normal form, Define Boyce codd normal form A relation...

Define Boyce codd normal form A relation schema R is in BCNF with respect to a set F of functional dependencies if, for all functional dependencies in F + of the form.α ->β.

Differance between unordered and ordered file, Differance between Unordered...

Differance between Unordered and ordered file ? Unordered file do no has any sequence although ordered file has arranged in a few sequence and data are assigned in ordered form

Advantages and drawbacks of ddbms, Advantages And Drawbacks Of Ddbms  T...

Advantages And Drawbacks Of Ddbms  There are various reasons for building distributed database systems, with sharing of data, reliability and availability, and speedup of query

Draw enhanced er-diagram for hierarchy of a student database, Draw an EER d...

Draw an EER diagram that captures the "is-a" hierarchy of students in another simple database. The database captures both the "basic" information (say, student ID and student name)

Normalization e, explain normalization,and give the examples 1NF,2NF,3NF,BC...

explain normalization,and give the examples 1NF,2NF,3NF,BCNF.AND FUNCTIONAL DEPANDENACY AND DECOMPOSITION TECHNIQUES.

What is multivalued attribute, What is Multivalued Attribute? Multival...

What is Multivalued Attribute? Multivalued Attribute - Multivalued attribute might have more than one value for an entity. For instance, PreviousDegrees of a STUDENT.

What is the need for triggers, What is the need for triggers? Triggers ...

What is the need for triggers? Triggers are useful mechanisms for alerting humans or for starting particular tasks automatically when particular conditions are met.

Describe the types of attributes, Describe the types of attributes? Ty...

Describe the types of attributes? Types of attributes: An attribute's category determines the type of values that are permitted in the attribute. For instance, the value vers

Find out the names and company names from database, Find out the names and ...

Find out the names and company names of all employees sorted in ascending order of company name and descending order of employee names of by which company. SELECT EMPLOYEE_NAME,

Using relational algebra which query finds customers, Using Relational Alge...

Using Relational Algebra which query finds customers, who have a balance of over 1000 ? Using Relational Algebra Π Customer_name( σ balance >1000(Deposit)) is query to find cu

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