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Transaction Processing Systems
Definition (collect, store, modify and retrieve the transactions)
Two types
o Batch processing
o Real time processing
 Concurrency
 Atomicity
 Transaction processing Monitor
Characteristics of transaction processing systems
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Rapid Response
Reliability
Inflexibility
Controlled processing
Data Validation
 Transaction initiation
 Field checking
o Range check
o List check
o Type check
o Check digit
Historical Significance of TPS
 UNIVAC
o John Presper Eckert and John William Mauchly
Manual Transaction Systems
 POS
o 11 steps
Examples of Transaction processing Systems
Components of a TPS
 Users
 Participants
 People
Examples of Real Time Transaction Processing
 Reservation systems
 POS terminals
 Library Loan Systems
Examples of Batch Transaction processing
 Cheque clearance
 Bill generation
 Credit card sales transactions
Storing and Retrieving
Databases and Files
 Definition of a database
 3 main types of databases
o hierarchical databases
o network databases
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o relational databases
good database design necessary to find correct information
o good data placement
o short transactions
o real time backup
o high normalization
o archiving of historical data
o good hardware configuration
5 basic types of files
o A master file
o Transaction file
o Report file
o Work file
o Program file
Data Warehousing
 Different data sources
 Collected real time
 Provides data that is:
o Consolidated
o Subject oriented
o Historical
o Read only
Backup Procedures
 Minimize disruptions
 Regular
 Can rebuild system
 Should be stored offsite or separate location.
 Recovery Process
o Periodic backup
o Journals
o Checkpoint
o Recovery manager
o 2 types of recovery
 backward recovery
 forward recovery
 magnetic tape still most commonly used
 Grandfather-father-son
 Partial backups
Updating in a Batch
 2 stages
o collecting and storage of transaction data
o Processing of the Data
 Involves sequential access (often stored on tape)
 Updating in Real Time
 Involves large numbers of users
 Direct access (random access)
Other Information Processes
Collecting
 Hardware
o MICR (magnetic ink character recognition)
o ATM (automatic teller machine)
o Barcode reader
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Forms
o Paper forms
o E-forms (on screen forms (web forms, database forms)
Analysing Data
 Decision Support Systems (DSS)
o Data Mining
o Data warehousing
 Management Information Systems (MIS)
o Common examples of MIS output include: reports on sales, stock inventory, payroll, orders and
budgets
o Types of reports include
1. Scheduled reports (printed on regular basis)
2. Forecasting reports (to make business forecasts)
3. On-demand reports (generated on request)
4. Exception reports (to alert people to special events)
Issues Related To TPS
Nature of Work
 Automation of jobs
o Job losses
o Need for training to keep up with changes
 People as participants
o Cash transactions at ATMs
o Internet purchase
o Web forms
Non Computer Procedures
 Still used during breakdowns
 Some times easier not to use TPS
Bias
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Data must be bias free
Not skewed
o Charts must use appropriate scale
o Tables must contain relevant details
Ethical issue when data is knowingly misrepresented
Importance of Data
 Data Security
o Encryption during transmission
o Firewalls to authenticate access
o Passwords
o Biometric devices
 Data Accuracy
o Data should be free from errors
o Use data validation techniques to reduce data entry errors
 range checks,
 list checks,
 type checks,
 check digits
o Use data verification techniques to ensure data is up to date
o Opportunities need to exist to change and update data if it is wrong.
 Data Integrity (describes reliability)
o ACID test
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Atomicity
Consistency
Isolation
Durability
Control in Transaction Processing
Needed to safeguard accuracy
To safeguard against corruption and fraud
The organisation should not be dictated by TPS