Data Collection and Preparation

Data Input

Data processing and StorageData Output

The Data Processing Cycle

• If data printed or written down on paper, that paper is called a Source Document

• Source documents need to be laid out clearly to avoid mistakes

Data Collection and Preparation

Examples of Source Documents:

•Application forms

•Mail-order return slips

Input: Direct Data Input

•Inputting data directly means that fewer mistakes are made.

•Bar codes

•Mark sense cards

•Magnetic stripe

•Smart Card

Validation: • Check Digits • Field checks • Range checks

Verification: • Entering data twice

Input: Making sure data is correct

• Character Recognition is used when documents also have to be read by humans

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Magnetic Ink Character Recognition (MICR)

Optical Character Recognition (OCR)

Input: Character Recognition

Data Processing and Storage

•A file is an organised collection of data arranged according to a particular structure The units of data which make up a file are called records Each record contains a number of separate items of data called fields

Data processing and Storage

•Interactive Processing- data is processed as the transaction is entered Batch processing –a large number of transactions are dealt with in one operation

•Sequential Access – Data stored on tape

•Random Access – Data stored on disk

• Paper • Screen • File

Data Output

• Network manager • Systems Analyst • Programmer • Engineer

Jobs

• Fraud • Hacking • Viruses, Worms, Trojans, Spyware • Denial of Service Attack

Crime

On-line Shopping -AdvantagesAdvantages to customer:

•Convenient

•No travel needed •Can compare prices

Advantages to company: •Lower costs •Open 24 hours a day

On-line Shopping (Disadvantages)

•Fraud

•Delivery problems

•Returning goods

On-line Banking

•Transfer money

•Pay bills or standing orders

•Check statement

Advantages for banks:

•Always open

•No building needed

Disadvantages of On-line Banking

•Phishing (Obtaining user passwords and bank details by fraud)

•Loss of personal contact

Automatic Teller Machine (ATM)1.Terminal reads data from card.

1.Customer enters PIN number and transaction details.

1.Data is encrypted and sent to main office over a dedicated telephone line.

1.Account and PIN number are checked, then balance is checked.

1.Authorisation is sent to terminal.

1.Terminal issues cash and returns card.

1.Confirmation sent from ATM to main office

1.Account has transaction

Electronic Funds Transfer at Point of Sale (1)

EFTPOS

1.The bar code on the product is scanned

1.The product code is sent to the till

1.The file of product records on backing storage is searched for a product record which matches the code

1.The price and name of the item are printed on the receipt

1.The number of items in the stock record is reduced by one

EFTPOS

Electronic Funds Transfer at Point of Sale (2)

6.Total of purchases is calculated

6.Terminal reads data from card.

6.Terminal checks for stolen cards.

6.Terminal checks amount on bill against floor limit.

6.If amount spent is over limit, terminal dials customer's bank for authorisation.

6.Details of purchase and customers bank account are stored on hard disk.

6.Receipt is printed.

6.Every night, bank is dialled up and information about the days transactions are transferred for batch processing.

Benefits of EFTPOS

•payment guaranteed by system

•less paperwork

•quicker than cheques

•smaller queues •less cash in store

•itemised bank statements

Payroll processing

Transaction file:

–Hours worked

–Overtime –Bonus

–Tax code

–Total pay to date

–Tax paid to date

Empty Transaction file

Payslip

Instructions to Bank

Master File

–Employee details

–New total pay

–New tax paid to date