Briefly describe concurrency execution, Database Management System

Assignment Help:

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 to two modes

Ø   Shared

Ø   Exclusive

T1 : lock - x(B );

read(B);

B:=B-50;

write(B);

unlock(B);

Lock-x(A);

read(A);

A:=A+50;

write(A);

unlock(A).

 

 


Related Discussions:- Briefly describe concurrency execution

State about the activity diagram, State about the Activity Diagram Act...

State about the Activity Diagram Activity diagrams show flow from one activity to other. It is an ongoing non atomic execution within a state machine. Activity finally results

What is primary index, Primary Index In primary index, there is a one-t...

Primary Index In primary index, there is a one-to-one relationship among the entries in the index table and the records in the major table. Primary index can be of two types:

Maping constraits, #question.what is mapping constraints and types?.

#question.what is mapping constraints and types?.

Division operation, To do the division operation R1 ÷ R2, R2 should be a co...

To do the division operation R1 ÷ R2, R2 should be a correct subset of R1. In the following example R1 have attributes A and B and R2 have only attribute B so R2 is a correct subse

The structured query language, The Structured Query Language INTRODUCT...

The Structured Query Language INTRODUCTION Database is an organised set of information about an entity having controlled redundancy and serves numerous applications. DBMS

Relational algebra and calculus, Q.  What is relational algebra and calcul...

Q.  What is relational algebra and calculus? Explain the relational algebra operators :- Selection and predicate, set operation, joins and division. Sol. Relational Algebra

Optimistic concurrency contents -write-set(t), write-set(T): Each data ite...

write-set(T): Each data items that are written by a transaction T

E-R Diagram, The H. I. Topi School of Business operates international busin...

The H. I. Topi School of Business operates international business programs in 10 locations throughout Europe. The school had its first class of graduates in 1965. The school keep

Strong entity set and weak entity set, Strong entity set and weak entity se...

Strong entity set and weak entity set? Strong entity set and weak entity set: A strong entity set has a primary key. All tuples in the set are distinguishable through that key.

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