Explain the timestamp ordering protocol, Database Management System

Assignment Help:

Timestamp Ordering Protocol

A timestamp is a tag that can be attached to any transaction or any data item, which indicates a specific time on which the transaction or data item had been activated in any way. We, who use computers, must all be familiar with the methods of "Date Created" or "Last Modified" properties of files and folders. Well, timestamps are things like that.

A timestamp can be executed in two ways. The simplest one is to directly assign the current value of the clock to the transaction or the data item. The other policy is to attach the value of a logical counter that keeps incrementing as new timestamps are needed.

The timestamp of a transaction shows the time when it was first activated. The timestamp of a data item can be of the following two types:

W-timestamp (Q): This means the latest time when the data item Q has been written into.

R-timestamp (Q): This means the latest time when the data item Q has been read from.

 


Related Discussions:- Explain the timestamp ordering protocol

Explain the three data anomalies, What are the three data anomalies that ar...

What are the three data anomalies that are similarly to take place as a result of data redundancy?  Can data redundancy be completely eliminated in database approach?  Why or why n

What are audit trails, What are audit trails? An audit trail is a log o...

What are audit trails? An audit trail is a log of all alters to the database along with information like which user performed the change and when the alter was performed.

What is outer join, What is Outer join?  They can be employed while we ...

What is Outer join?  They can be employed while we want to keep all the tuples in R, or all those in S or all those in both relations in the result of the JOIN in spite of of w

What is a view in sql and when can views be updated, What is a view in SQL?...

What is a view in SQL? When can views be updated? A view is a virtual table which consists of columns from one or more tables. Through it is same to a table; it is stored in

Identify the critical activities, Consider a systems development project wi...

Consider a systems development project with the following data Activity                                Duration (weeks)        Precedence Relationship 1. Software design

Prepare heart failure registry database, Prepare Heart Failure Registry dat...

Prepare Heart Failure Registry database How are you today? Please I would like you to design a Heart Failure registry where doctors will log in to enter information about their

Explain about data independence, Data Independence This brings us to ou...

Data Independence This brings us to our next topic: data independence. It is the property of the database which tries to make sure that if we make any change in any level of sc

Give an example of multiple inheritance, Give an example of multiple inheri...

Give an example of multiple inheritance.  One example of multiple inheritance is a committee for students affair which include faculty and administrative staff member.

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