ch 26. you should understand the differences between batch processing, online processing and...
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Ch 26
Objectives
You should understand the differences between batch processing, online processing and real-time processing, including: Billing systems Booking systems Payment systems Real-time systems
Types of processing
There are three basic types of processing: Batch processing Online processing
▪ This is sometimes known as transaction processing
Real time process control
Batch processing
1. With Batch Processing, a number of jobs are collected together over a period of time
2. They are loaded onto a computer system (in a job queue)
3. And then processed all at once (in a batch)
Once the batch processing starts, there is no need for any human intervention at all
It can only be done where there are no timing constraints (ie no response is needed from the computer right away)
Batch Processing
Examples of batch processing are:
the processing of bank cheques
payroll non-automatic stock
control systems utility billing
Batch Processing : Advantages
Can be performed at night when the computer system is not so busy
People do not need to be involved
Batch Processing : Disadvantages
Data is only up to date only when the batch processing has finished
Cannot produce adhoc reports
Online processing
Data is entered by the user, and the computer processes the data straight away.
Processing done as quickly as possible; booking of airline ticket or cinema ticket (these need to be marked as “sold” or “unavailable” immediately the booking is confirmed).
Sometimes called interactive processing
File is updated as each transaction is processed eg ATM, flight booking etc
Online Processing : advantages and disadvantages
Type of processing
Advantages Disadvantages
Online/ Interactive Processing
Immediate processing, up to date data
Files held online, can do ad hoc reports
Audit trails hard to perform
Very little paperwork, so harder to check for errors, etc
Examples of Online processing
Flight bookingsCinema bookingsTheatre bookingsATM withdrawals
How an online booking system works
Online booking systems rely on the ability to update files immediately, in order to prevent double-booking of seats etc
There are a number of steps involved: the order of these is important
Online booking: steps 1
Customer logs on to theatre website and clicks on required performance
Enter date & time + number of seatsSeating display: choose seats If seats are available, seat numbers
and price are displayedCustomer clicks ‘confirm’Seats are now set temporarily in the
theatre database as ‘unavailable’
Online booking: steps 2
Customer enters personal details (eg username & password
Select payment method & make payment
EFTPOS system contacts customer’s bank and enquires if funds are available
Payment is confirmedReference number onscreen/emailDatabase updated with the
transaction
Real time Process Control
The computer responds instantly to events occurring. E.g. Flight simulator
Usually involves sensors and feedback loops
Real time mode is used in computers that have to react very quickly to inputs requiring immediate outputs (e.g. aircraft ‘fly-by-wire’ controls).
Real time Process Control (advantages and disadvantages)
Type of processing
Advantages Disadvantages
Real Time Processing
Reaction to input
Input can be from sensors – automatic feedback loop possible
Can be done by an embedded microchip in small home appliances
Expensive to develop
Very fast processor required
Real Time Processing
Examples of real-time processing are any control system which uses sensors requiring immediate response e.g.
Rockets fired onto space Robots Computer controlled air
conditioning / Central heating / burglar
alarm Computer controlled
greenhouses etc.
Examples of processing types
Energy / Electric company
Theatre Air line
Batch Processing
Printing electric bills
Setting up seating plan for new play
Setting flight schedules
Online Processing
Bill enquiry system
Seat enquiry system
Flight enquiry system
Real time Process Control
Power plant temperature management
Air conditioning
Autopilot
Criteria for choosing processing methods
Things to consider when choosing a processing method:
1. Whether information needs to be up to date at all times
2. Scale of the operation: Batch systems suited to processing of huge amounts of data
3. Cost: Real time system more expensive; more complex backup and recovery procedures required
4. Computer usage: Adv of batch, can process overnight on mainframe computers
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