What is a transaction? , Database Management System

Assignment Help:

What is a transaction?

The Transaction is a unit of data processing. For instance, many of the transactions at a bank may be withdrawal or deposit of money; transfer of money from A's account to B's account etc. A transaction would include manipulation of one or more data values in a database. Therefore, it may need reading and writing of database value. For instance, the withdrawal transactions can be written in pseudo code as:

Example:

; Suppose that we are doing this transaction for person

;  whose account number is X.

TRANSACTION WITHDRAWAL (withdrawal_amount)

start transaction

IF X exist then

READ  X.balance

IF   X.balance > withdrawal_amount THEN

 SUBTRACT withdrawal_amount

WRITE X.balance

COMMIT

ELSE

         DISPLAY "TRANSACTION CANNOT BE PROCESSED"

 ELSE DISPLAY "ACCOUNT X DOES NOT EXIST"

End transaction;

Another same example may be transmitting of money from Account no x to account number y. This transaction may be written as:


Related Discussions:- What is a transaction?

Clinic, Need a sample of a clinic database relationships

Need a sample of a clinic database relationships

2phase locking, we need example of 2phase locking

we need example of 2phase locking

Question, I want to buy this but I want to see a couple sample questions fi...

I want to buy this but I want to see a couple sample questions first. http://www.expertsmind.com/library/what-happens-to-rms-error-for-the-training-data-set-51564843.aspx

The average amount of their orders , Make SQL statements for the following ...

Make SQL statements for the following scenarios. Your response should contain SQL statement, output and any other assumptions you have made to arrive at the answer. For Colorado cu

Large Project, Can you help me with the following: Drop statements for all...

Can you help me with the following: Drop statements for all objects in the lab project. Create statements for all objects of the lab project Create indexes for foreign keys Cre

Define a relation in dbms, Define a relation ? Relation - A relations...

Define a relation ? Relation - A relations is a named two-dimensional table of data. Mathematically, a relation can be described as a subset of the cartesian product of a lis

Query processor in database management system, Query Processor The qu...

Query Processor The query language processor is responsible for taking query language statements or shifting them from the English-like syntax of the query language to a form

State the objectives-data source, You will be analysing a set of financial ...

You will be analysing a set of financial data of your choice. It is not necessary to collect any primary data of your own, and publicly available secondary data will be sufficient

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