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 the process of rearranging classes and operations, State the process ...

State the process of Rearranging Classes and Operations The various, yet similar operation of different classes can be slightly modified thus that they can be covered by a sin

Foreign keys , Foreign Keys and NULL Let us take the relation:         ...

Foreign Keys and NULL Let us take the relation:                 DEPT DEPT ID DNAME BUDGET D1 M

Explain the concept of deadlock, Question: In a multi-user database env...

Question: In a multi-user database environment, locking mechanisms can be used to solve the three basic problems of concurrency. On the other hand, however, locking may also le

What is theta join explain, What is theta join explain? Theta  Join  -...

What is theta join explain? Theta  Join  - The  theta  join  operation  is  an  extension  to  the  natural-join operation which permits us to merge selection and a Cartesian

Explain what is rdbms, Explain what is RDBMS ? RDBMS - RDBMS is a datab...

Explain what is RDBMS ? RDBMS - RDBMS is a database management system (DBMS) which stores data within the form of relations. Relational databases are powerful since they need f

Demonstrate the design of associations, Demonstrate the Design of associati...

Demonstrate the Design of associations During object design phase we must design a strategy to implement associations. Association may be unidirectional or bi-directional. Wha

State the two-way associations, Two-way Associations Mostly, associati...

Two-way Associations Mostly, associations are travel in both directions, although not usually with same frequency. There are three approaches for the implementation. In

Why is database redesign necessary, Why is database redesign necessary? ...

Why is database redesign necessary? Database redesign is essential for two reasons. First, redesign is essential both to fix mistakes made during the initial database design. S

What are called index-sequential files, What are called index-sequential fi...

What are called index-sequential files? The files that are ordered sequentially with a primary index on the search key are known as index-sequential files

Database incident table, The Incident table, with an auto-incrementing in...

The Incident table, with an auto-incrementing incident number, etc, looks like: incident_num reporter date time incide

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