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?

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

Explain relational model and their use in dbms, Explain Relational model an...

Explain Relational model and their use in DBMS? Relational Model - The relational model was first introduced through E.F. Codd of the IBM Research in the year of 1970. The mode

Emergence of client server architecture, Emergence of Client Server Archite...

Emergence of Client Server Architecture Some of the pioneering work that was completed by some of the relational database vendors permitted the computing to be distributed on m

Types of indexes, Types Of Indexes One of the words used during the fil...

Types Of Indexes One of the words used during the file organisation is the term index. In this part, let us describe this term in more detail. We find the index of keywords

Need vmware technical support, Project Description: Critical Project for...

Project Description: Critical Project for VMware Technical support. VMWare ESXi 5.1 support for upgradation and migration problem. Technical expert of Vmware needed. Sk

Explain consistency model , Explain in detail the consistency model of the ...

Explain in detail the consistency model of the distributed file system you studied (GFS or AFS). Present the consistency model chosen and how it was achieved through design. Clarit

Functional dependencies and normalization for relational dat, Consider the ...

Consider the 1ollowin8 relation: CAR SALE (Car_id, Option_type, Option_listprice, Sale_date, Option_discountedprice) This relation refers to options installed in cars (e.g., crui

Principles of good e-governance, Question: (a) e-Government implementa...

Question: (a) e-Government implementations normally evolve through a multi-stage process. Describe, using appropriate examples, the stages involved in an e-Government implemen

Explain record based logical models, Explain Record Based Logical Models? ...

Explain Record Based Logical Models? Record-Based logical Models: Also define data at the conceptual and view levels. Unlike object-oriented models, are used to state overall

Explain the cartesian product, Explain the Cartesian product:  The Cart...

Explain the Cartesian product:  The Cartesian product operation does not need relations to union-compatible.  The meaning of this is that the involved relations may have dissim

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