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?

Data control, Data Control The data control mostly refers to commands that...

Data Control The data control mostly refers to commands that permit system and data privileges to be passed to several users. These commands are usually available to database admi

Data fragmentation in distributed database system, brief history,definition...

brief history,definition,current trends and future trends if any of data fragmentation

What are the advantages of dbms, What are the advantages of DBMS ? 1. ...

What are the advantages of DBMS ? 1. Centralized Management and Control - One of the major advantages of using a database system is in which the organization could exert, thr

Describe drop table command or cascade of sql, Describe DROP TABLE command ...

Describe DROP TABLE command of SQL along with both the options - CASCADE and RESTRICT. DROP TABLE command - This command drops the specified table. Dropping a table also dro

Project operation, The PROJECT operation The project operation is used t...

The PROJECT operation The project operation is used to choose the records with specified attributes as discarding the others based on some related criteria. This is denotes as ∏

Perform an exploratory analysis on the entire dataset, Australian Bureau of...

Australian Bureau of Statistics (ABS) provides retail data for different groups and different states as well as the aggregate numbers. Table 11 " Retail Turnover, State by Industry

Which language has recently become the defacto standard, Which language has...

Which language has presently become the defacto standard for interfacing application programs along with relational database system? The language which has recently become the

Compute the closure set, Compute the closure (F+) for the following set of ...

Compute the closure (F+) for the following set of the functional dependencies defined on R(a,b,c,d), where F - {c→ a, ab → d, a → b, d → c}, i.e. what are all of the FDs implied b

Binary relationship, explain in details about one to one binary relationshi...

explain in details about one to one binary relationship

What are the different integrity constraints in rdbms, What are the differe...

What are the different integrity constraints in RDBMS? The various integrity constraints in RDBMS are as: Primary Key: primary key is a grouping of one or more attributes

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