Transcript Document

Commercial Data Processing
Learning Objectives
• Use of computers in organisations
• Need for Commercial Data Processing
• Difference between data and information
• Description of
Commercial Data Processing
CDP is the processing (handling) of a huge amount of data.
The Need for CDP
• Process information at high speed
• Handle repetitive tasks
• Can work continuously and produce accurate results
• Access data at a high speed
• Can handle a large volume of data
• Store large amount of files
Learning Objectives
By the end of the period I will be able to…
• Discuss the main parts of the CDP cycle
• Aware of different organisations that use CDP>
Who uses CDP?
• Bank
• Supermarkets
• Airlines
• Police
Data and Information
Data is a general term for numbers, characters,
symbols, graphics and sound which are accepted
and processed by a computer.
Information is given the data a meaning.
Data 95100 (for computer)
Information £95100 (for people)
The Data Processing Cycle
Data collection
and preparation
Data Input
Data Output
Data processing
and storage
Data Collection and Preparation
First stage of the CDP cycle is to collect data and prepare it
for the computer.
Source Document
Data printed or written on paper, for example, an order form.
These forms will be laid out clearly, so that people can fill out
without making mistakes.
Data Input
Stage 2 of the cycle where data is inputted directly to a computer,
less people involved.
• Bar Codes
• Mark Sense Cards
• Magnetic Stripes
• Smart Cards
• Character Recognition
Bar Code
A bar code is a set of lines of varying widths, which can be read by
passing a bar code reader across them. Used to identify goods in a
shop.
Price will not be programmed into the bar code
a) Country
b) Manufacture
c) Product
5 0 1 123 4 89 3
a
b
c
d) Check digit
4
d
Check Digit
There to make sure the scanner has read the bar code properly. Uses
the other numbers in the bar code to calculate the check digit.
Mark Sense Cards
Cards divided up into columns that allow spaces for marking
with a pencil line.
A machine, a mark sense reader reads the marks by an
optical scanner.
Example
Useful for collecting data (multi-choice type questions)
Lottery Tickets
Magnetic Stripe
A magnetic stripe on which data is held. The
stripe can hold about 64 characters.
Bank card would hold the sort code and the account number.
Store card would hold the customers account number
Smart Cards (chip cards)
A smart card has its own processor, and is able to store
much more information than fits on a magnetic stripe.
Smart cards can be used instead of cash this is known as
electronic purse.
Cash can be reloaded onto the card from a machine.
Banks are also using smart cards in addition to the stripe.
More difficult to forge. Information is stored in a chip, which
are not easily damaged.
Character Recognition
Process of recognising characters by a computer. The characters will
not make sense to people.
Examples
• Magnetic Ink Character Recognition (MICR)
• Optical Character Recognition (OCR)
Magnetic Ink Character Recognition (MICR)
An input process which can read characters written in magnetic
ink.
The number along the bottom of a bank cheque are printed in
magnetic ink.
A magnetic ink character reader is used to input the information
into the computer.
Magnetic ink is difficult to forge
Optical Character Recognition (OCR)
An optical character reader is able to recognise letters and numbers
and read then directly onto a computer.
Mistakes can be made if the letters and numbers are badly formed.
You can use a scanner with suitable OCR software to read in pages
of text to a word processor.
Data can be stored in the form of a file, record and a field.
Back Up
A second copy of a file, incase the original is lost, stolen or damaged
Validation and Verification (Credit)
Validation
Checking the data is sensible and accurate. Does not eliminate
mistakes, but make it difficult for wrong data to get through.
Example is range check and check digit.
Verification
Checking the data has been entered correctly. Entering the same
data twice is a way of verifying data.
Verification is most often used to confirm a new password.
Making sure data is correct!
Data entered into a computer must be correct. The process of making
sure the data is correct is called error checking.
• Check Digit
• Number Check
• Range Check
Check Digit
A check digit is an extra digit which is calculated from the original
numbers and put and the end of that number.
2954
2+9+5+4 = 20 + 1
= 21
Check digit is 1
29541
Number Check
Used in database field to specify the number of characters allowed in a
field.
Postcode Max - 6 characters
Range Check
To check the numbers are sensible
• Age <50 >16
• Date <1
>31
Data Processing and storage
The third stage of the cycle which involves the process and storage of
data.
Database
FILE is an organised collection of data.
RECORD is an item which makes up a FILE. An individual card.
FIELD is the separate items that make up the record.
Interactive Processing
A method of processing information. Data is processed or updated as
the transaction is entered, and any enquires are replied to at once.
An example is booking a airplane ticket or lifting money from a cash
machine.
Reading Data
Two ways of reading, or accessing data files:
Sequential Access and Random/Direct Access
Sequential Access
The user would have to go through all the records in sequence to get to what
they want. An example of this is magnetic tape
Random/Direct Access
Data can read directly without having to work through the other data. Optical
disk is an example of this.
Multi User Database (credit)
A multi-user database is one which can be accessed by many users
at the same time.
For this to work the database must be stored centrally, for example, on
a mainframe or a server.
User cannot change the same record in the file. If this happens one
user will be locked out.
Data Output (4th Stage)
After the data has been processed, the information can
be outputted on:
• Paper
• Screen
• Saved as a file
Paper
Information for customers, like bills or statements, is
normally outputted in printed form.
Businesses use pre-printed stationary
Banks, stored card companies etc use pre-printed stationary
to send of to their customers. This is paper with printed
information on it. Customer account number, name and
address.
Screen
Information can be outputted onto a screen.
Banks use electronic billing for their customers through
the internet.
This can save the company money, no need to send
their bills using the postal service.
File
Instead of outputting data to a printed or displaying it on a
screen it can be saved as a new file.
This can be held on a disk of magnetic tape.
Can be used at a later date.
Hardware and Software Used
Hardware used for CDP consists of a MAINFRAME. A
mainframe computer is made up of several devices:
•Central Processing Unit (CPU)
•Input Devices
•Output Devices
•Backing Storage Device
•Terminals
•Operator Console
Terminal
These are used for data input. Consist of a keyboard
and a screen. Do not have own processor.
The do not have to be in the same room as the mainframe.
The can be in a different building. This is known as remote
terminals.
Multi-User Access
Many users using the same system at the same time.
Implications of CDP - Social
Can cause major problems to businesses. The introduction
of computers can cause:
Disadvantages
Advantages
Job Lose
Employees learn new skill
Employees need retrained
More competitive
Up-keep of computers
On-Line Banking
Fear of computers
On-line Shopping
Implications of CDP – Economic
Initial Cost
The cost of setting up the system are extremely high.
• Training
• Hardware & Software
• Maintenance (running cost)
Security and Privacy
All large companies hold data about their employees.
Companies would therefore have to register with the Data
Protection Act
• Accurate
• Up-to-Date
Sale of Customer List
Companies sell there data to other companies. Data such
as names and addresses of current customers. This is why
we get so Junk Mail.
Job Types and Careers
The introduction of computers has introduced many new
types of jobs.
• Network Manager
• Systems Analyst
• Programmer
• Engineer
Network Manager
Person in charge of the network. Responsible for all
computers attached to the network. Decides usernames and
passwords along with access levels.
Systems Analyst
Plans how the computer system will be used within a
company.
• Visit company and examine how the manually carry out
tasks (systems analysis).
• Chats to staff.
• Write a report with details of cost of installation.
• Once system has been installed the analyst will look for
ways to improve the system.
Programmer
Will write or buy(off the shelf) the programs specified
by the systems analyst.
He will check programs have no mistakes and take them out
(debugging)
Programmer will write documentation for the program so
people can understand how to use it.
Engineer
Visits the company to repair and inspect computers.
Maintenance contracts are usually set up with a company.
Computer Crime (Credit)
Fraud
Computers can be destroyed, corrupted or files changed.
Money can be stolen by computer fraud.
Hacking
Gaining access to a computer system from anywhere outside
the company, usually via the internet.
Companies can make hacking less easy by changing their
security passwords regularly and keeping them secure.
Virus
A program that someone has deliberately
created. A computer virus is able to make
itself invisible to the computer until it
passes into the memory of a host
computer.
Electronic-Commerce (e-commerce)
Process of conducting business on-line.
• On-Line Shopping
• On-Line Banking
On-Line Shopping
Process of purchasing goods from the
internet.
Process of On-line Shopping
• Search for produce
• Select produce and checkout
• Give name, address and bank details
• Choice of delivery
• On completion you will be sent a
confirmation e-mail
Paying for your purchase
• Cheque guarantee card
• Cash Card
• Credit card
• Multifunction card
• Debit card
Advantages and Disadvantages for companies
Advantages
• No need to employ staff
• No need for premises
• Larger choice
• Impulse shopping
Disadvantages
• Bank Fraud
Advantages and Disadvantages for customers
Advantages
•24 shopping
• Large amount of products
available
Disadvantages
• Bank Fraud (card holder
not present)
• Have to wait to receive
good by post.
• can compare prices
•Have to return good
through post.
Electronic Funds Transfer (EFT)
Automatically moving money from one account to another
using a computer system where no cash changes hands.
Point of Sale (POS)
Place in a shop where the goods change hands.
Checkouts.
Electronic Point of Sale System
This is the name given to the computerised system used
within shops.
• Use bar codes
• Scanner reads the data from the bar code
• Computers are connected to checkouts
• Itemised receipt
Advantages of EPOS
Disadvantages of EPOS
• Quicker and easier for
shopper
• Mistakes can be made at
the pricing stage.
• Itemised Receipt
• Multi packs must have
separate bar codes
• Shop can keep records of
sales
• Sales can be set up
easily
• Fewer staff needed
• No need for shop keeper
to remember prices.
Electronic Funds Transfer at Point of Sale (EFTPOS)
A way of paying for goods using a bank card instead of
cash.
Advantages of EFTPOS
Disadvantages of EFTPOS
• Payment is guaranteed
by the system
• Expensive to install
• Less chance of theft
• Easy to overspend!
• Customer has to keep
• Less paperwork, no cash, track of account-does not
come off account for 2 days
no cheques
Implications
Initial Cost
• Price of setting up the system are high
• Hardware and software are expensive
Running Cost
• Hardware needs maintained
• Software licenses renewed
• Electricity
• Paper
• Toner
Implications - Security and Privacy
Data Protection Act
All companies hold data about their employees and
customers on computer. Any information which a company
holds must be registered under the Data Protection Act.
Data must be:
• Accurate
• Kept up to date
• Kept private
Physical and software security
Data kept in a secure place, for example:
• Locked room
• Protected by password
• Encryption
• Different levels of access
Sale of Customer Lists
Companies sometimes sell their lists of customers names
and addresses to other companies.
This is how junk mail originates.
Advertising Standards Authority imposed strict regulations on
sales of customer lists.
• Person must be told
• Person has the right to stop their name being used
• The company must remove his/her name if asked.