Transaction Processing Systems
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Transaction Processing Systems Transaction processing systems are information systems which collect, store, modifies and retrieves the daily transactions of an organisation. TPS's are all to do with business, money and most importantly securing and recording the daily transactions of a company. This topic focus' on the processes of storing and retrieving, collecting and analysing. Contents 4.1 Characteristics of Transaction Processing Systems 4.2 Examples of Transaction processing Systems 4.3 Storing and Retrieving 4.4 Other Information Processes 4.5 Issues Related to Transaction Processing Systems HSC Questions on TPS News forum TPS Teaching Program TPS Outline Year 12 Assessment Task includes Multimedia Glossary TPS TPS Topic Test
4.1 Characteristics of A Transaction Processing System Four important characteristics of a TPS are: Rapid Response 1 Reliability Inflexibility Controlled Processing
Batch Processing Real-time Processing Transaction Processing Monitors Data Validation Manual Transaction Systems Questions for 4.1 Batch Processing Vs Real Time Processing Batch Processing: was developed early on when computers were scarce and computing time was expensive. batch processing reduced costs by reducing the time for user input. In batch processing all the information that needs to be processed is collected and processed as a batch (group) at a later time.
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This machine shown above was used by US Agricultural Department to store statistics on erosion. You can see how all the punch cards are processed together. Real Time Processing: The processing occurs on the spot at that time. Examples of real time processing in TPS systems are EFTPOS machines and ATMs such as is happening in the image. When goods are purchased using EFTPOS the transaction occurs on the spot. 2 main concerns with real-time processing are: concurrency: ensures that more than one user cannot change the same data at
the same time. atomicity: all the steps in a transaction are completed or no transaction takes place and any changes do not go through. HSC Questions Transaction Processing Monitor This is software used to initiate and monitor the transaction inorder to reduce errors and is sometimes referred to as middleware. TP monitor technology controls transaction applications and performs business logic/rules computations and database updates in distributed client server environments. TP monitor technology is used in data management, network access, security systems, delivery order processing, airline reservations, and customer service.
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Data Validation this is the process of checking the accuracy of entered data. This involves software called a transaction processing monitor (TPM) and requires 2 processes: Transaction Initiation: This is like a communications handshake and sets up the protocols and acknowledges the readiness of the system to send and receive the transaction data. This is used to reduce and help eliminate errors. Times are added as headers in the data to allow the data to be traced in the evnt of data loss. 4 Field Checking: This occurs as data is entered into the database to ensure as far as possible that what is entered makes sense. There are a number of different checks made including: range checks, list checks, type checks and a check digit. Range Check: Checks that the data lie within a specified range of values, e.g., the month of a person's date of birth should lie between 1 and 12. Check Digit: Used for numerical data. An extra digit is added to a number which is calculated from the digits. The computer checks this calculation when data are entered, e.g., The ISBN for a book. Type Check: Checks the data type is the correct type such as data entered in a text field is text, numbers in a numerical field.
List Check: used to compare what is entered compared to a set of accepted data (i.e. a list). This list may include the states of Australia, Months of the year, names of capital cities. Data Validation Questions HSC Questions on Validation and Verification Manual Transaction Systems Manual transaction systems are business systems which operate without an information system (i.e. no computers). They have been around for thousands of years. The earliest writings are Sumerian business receipts on clay tablets which are around 5 thousand years old. But of course people still keep manual transaction records. You probably keep receipts for goods that you buy. You may keep these for tax reasons or for warranties but either way they are transaction records. Most people still keep a range of receipts on paper. Until recent times many records were still stored in account books. This required bookkeepers to 5 balance the accounts. These are the manual equivalent of spreadsheets. However these days most companies are electronic whether it be buying a seat on a plane or purchasing a book. Transferring these paper based records into an electronic system has many benefits including: customers can purchase goods at their convenience it is easy to do stocktakes reduced wage costs Whatever the peripheral benefits computerisation of a manual system will aim to maximise profits. 4.2 Examples of Transaction Processing Systems In this section we will look at components of a TPS and some real life examples. 6 Contents Components of a TPS Examples of Real-time Transaction Processing (reservation systems, POS, Library Loans)
Examples of Batch Transaction Processing
Questions for 4.2 Characteristics of a TPS Components of a TPS The components of a TPS include hardware, software and people. The most important component of a TPS are people. Without people the system does not have customers and without customers it does not have a funtion to perform. People in a TPS can be divided into 3 categories: users, participants and people from the environment. Users: The users are people employees of the company who own the TPS. They will use it to provide information information about the system but will not enter data themselves. The 7 information they provide from the TPS may be used to provide inputs for other information systems such as stock control, marketing etc... Participants: Participants are direct users of the system. These are the people who will enter the data. They include data entry operators, customer service operators, people working at checkouts and anyone carrying out the tasks required to process the data. People From The Environment: These are people who do not directly work for the company but people off the street who sometimes require the services of a TPS as they enter transactions and validate data such as a customer withdrawing money from an ATM. Examples of Real-time Transaction Processing There are 3 examples of TPS examined in the HSC:reservation systems, POS, Library Loans Reservation Systems These are used by businesses where services need to be booked. Examples of reservation systems can be found at travel agencies, airline companies, rental companies, entertainment agencies such as Tickatek or the relevant venues. Every time a booking is made the available resources need to be reduced by the same number or resources reserved or paid for. Once the transaction has 8 taken place then tickets need to be printed credits will be transferred from the customer's account to the booking agency, receipts need to be printed and transaction records need to be updated in the database. Point of Sale (POS) POS is the system that is in place for purchases involving EFTPOS (electronic funds transfer at point of sale). POS is just an abbreviation of the full name of EFTPOS. POS systems are found in many businesses now from major outlets such as Coles or Woolworths to many mixed businesses and petrol stations. The POS system is what allows the convenience of an ATM at midnight. When a transaction takes place, goods are scanned from barcodes or details are typed in, any required
credit card checks are made, a receipt is sent to the customer (displayed on the screen or printed on a receipt), coded inventory data is sent through to update the database and the inventory or bank balance is updated. It will also work out the change required and any receipt will normally itemise items. Library Loans The borrower will normally have a library membership card which will be scanned and checked for overdue books and fines, the borrowed items will be scanned and each item will then be placed under the borrowers name. The details about available books will then be updated on the database. The system will also allow reservations to be placed on the books. Examples of Batch Transaction Processing Contents Cheque Clearance Generation of Bills Credit Card Transactions There are three examples that the NSW HSC syllabus refers to: cheque clearance, bill generation and credit card sales transactions "examples of batch processing, including: clearing of presented cheques 9 generation of bills systems that appear real time, computerising transactions as they occur, but actual updating is processed in batch, such as credit card transactions" HSC syllabus page 45 Clearing of Presented Cheques (Cheque Clearance) Once a cheque is presented to a bank it is normally put to the side and processed as part of a batch. In fact the cheque will become a part of one batch once it is deposited at the bank and then part of another batch once it is sent to the issuer's bank. Each step has built in delays to ensure that people are not paid twice or the money taken out of an account which does not have the money. These days, will electronic processeing cheques are normally cleared within three days it use to take over a week. Generation of Bills
Bills are not pleasant. For many people it always seems that many bills appear at once. This is not coincidence but you will be glad to know that it is not part of some evil plot. Most bills are generated for a fixed time period which the computers will automatically generate once that period has fallen due. Once there is an overlap of bills they will continue to come at the same time because that is how they are generated: as a batch for a fixed time period. The bills are generated as a batch to reduce mailing and printing costs. Some companies will even allow users to view their bills and account details online. Credit Card Transactions Credit card transactions on the internet are very unusual because they appear real time but in fact are actually batch. Huh? Seems strange doesn't it. But in reality the only real time transaction is the check that is made to ensure that the card is current, and is not listed as lost, stolen, cancelled or over the limit. The transaction i8s actually processed as a batch at a later stage. Of course there are still manual credit card transactions which are entered into the TPS. these transactions may take from hours to weeks before they are processed. The manual aspects to online credit card transactions bring in issues of security (credit card fraud, identity theft), privacy (personal details can be read) and ethical issues.
Case Study Students create their own virtual case studies including feasibility studies, and presentation to virtual executives of organisation. sample PowerPoint for a case study 1 0 Laura's Liquorland TPS notes from Andrew Rebecca TPS PowerPoint Celia PowerPoint 4.3 Storing and Retrieving many people daily rely on the reliability of TPS and as such they must have an efficient and safe 1 method of storage and retrieval. Databases are 1 used to store the data and requires a safe and effective plan for backups and recovery if anything goes wrong.
Contents Databases and files (hierarchical, network or relational structure, Good Design) Data warehousing Backup Procedures Doing Updates (batch) Real-time Updates Worksheet for 4.3 Storing and Retrieving Databases and Files hierarchical, network relational structure Good Design For TPS Files and TPS' 1 2 A database is an organised collection of data. When an organisation stores its operational records and accounts in a databses this type of database is then called an operational database. The database is organised in a schema. The TPS will out of necessity have access to aspects of the database such as accounts and stock. Because the TPS only has access to a subset of the database this is called a subschema. There are 3 different types of schemas which may be used to organise the database structure; hierarchical, network or relational structure. Hierarchical Databases: are organised in a hierarchical or tree like structure consisting of nodes and branches. Each node can have many branches but the child node can only have one parent node.
Network Database: In networked databases the primary node in a branch is called the owner (parent) of that group with information relevant to that topic being a member of that level 0 node. The child nodes can be linked (member) of other groups.
Relational Databases: A relational database organises information through a series of related tables. Realtionships are formed between tables to link various types of information. Relational databases are the most commonly used type of database. A relational database consists of a
collection of tables that store particular sets of data. The invention of the relational database system has standardized the way that data is stored and processed. Most of the database management systems used today are based on the relational system.
Good Design For a TPS A good TPS must have several important characteristics: Good Data Placement: Commonly used blocks of data should be together to speed up data access rates. Short Transactions: Break up complicated and long transactions into shorter transactions to 1 improve processing time and concurrency. 3 High Normalisation: A high level of normalisation (reduction of redundant data) increases access rates, time taken for updates and concurrency for a database Archiving of Historical Data: Old data needs to be archived to reduce the overall physical size of the database which increases access (including queries and reports) and backup times. Good Hardware Configuration: The hardware should be physically capable of dealing with the demands placed upon it including enough physical space to store the data. Data Warehousing consolidated subject-oriented 1 4 historical read only Data is a valuable commodity which is traded and sold. This data ranges from personal information on customers, demographics on customer bases for products, sales figures and so on. All of this data is stored in databases called data warehouses. This data can then be used for a
myriad of reasons. Reports can be writtenn or marketing plans may revised all based on figures stored in a data awarehouse. AI programs are often used to look for meaningful patterns. people who look after these data warehouses are called Knowledge Managers. Data stored in data warehouses is used to look for patterns in credit card usage which points to fraud. Refer also to knowledge management , financial systems , data mining , Expert Systems A data warehouse provides data that is consolidated, subject-oriented, historical and read only Consolidated: data is organised in a consistent manner to allow usage of the data across organisations. Subject oriented: data is stored by subject to allow querying and reports. Historical: data is stored over a long time period. A longer time frame allows better analysis of the data. Read-Only: The data can not be changed by users. It can only be added to. HSC Questions on Data Warehousing Files and TPS' A file is a stored block of data. In a database a file is a set of related facts such as the details about on customer or the details about a particular loan, particular product etc... batch processing and real-time processing require different types of files and different ways to store and retrieve the information. TPS' have five different file types: Master File: This is the main copy of a database and is the main operational database for the TPS. A copy of transaction data must be stored in this file. 1 5 Transaction Files: This is a collection of the transaction records. This is used to update the transactions stored on the master file. Audirors will use these files to audit a companies transaction records. A Report File: A collection of data that has been formatted ready to print and present Work File: temporary file created during a transaction A program File: Contains code for the processing of data> This may be in SQL or another programming language. Backup Procedures Organisations using TPS are very dependent on the reliability of their systems. As such backup 1 procedures must be well planned and recovery procedures must have a minimal disruption to the 6 organisation Contents
Recovery Process Forward and Backward Recovery 3 Generations of Backups (grandfather, father Son) Partial backups Updating In A Batch Updating In real-time Recovery Process A TPS may crash or have errors for any number of reasons including: hardware failure, software failure, human error (such as entering the wrong data), viruses and worms or external problems such as power failure/ natural disaster such as flood. In order to deal with the failures the TPS must be able to restore correct data where possible. The recovery process is the process by which the database is restored back to a reliable configuration. The recovery process includes: Backups: A copy of the database is made on an ongoing basis. usually at least once a day when system is not used a backup of the entire system will be made. Journal: Journals record what happens in a database. There are two types of journals: transaction 1 logs which will record all the details about a transaction. Because a TPS is all about transactions a 7 transaction log will be long and detailed. Most of the time a transaction can be pined down to a rough time and then tracked from there. The journal roll from the register will form a hard copy of what is recorded. The second type is the database change log which shows changes made to the database. Remember most details in the database will not change very often. Checkpoint: Periodically throughout the day any information system will create checkpoints. All processing will very temporarily stop while all parts of the system are synchronised. When failures in a TPS occur the system can be restored back to the last checkpoint or any other checkpoint chosen. as such checkpoints should be very regular, at least several times an hour. Processing can then be resumed from the last checkpoint. Recovery Manager: This is a program used to restore the database back to the chosen checkpoint. Forward and Backward Recovery There are two types of recovery procedures: backward recovery and forward recovery. 1 8 Backward Recovery: is used like an UNDO Button for a TPS. With a backward recovery the database administrator will try to undo unwanted changes. Forward Recovery: is like a REDO button where lost transactions are covered from the trasnaction
journal and the backup. 3 Generations of Backups (Grandfather-Father-Son) Grandfather-father-son is a backup system where 3 generations (backups made over 3 differnt times) where the grandfather is the oldest and the son is the most recent backup. The phrase is a general one and many more than 3 generations may be saved. Sometimes the most recent backup 1 is not the one we want. It maybe that for some reason an error crept into the system and it is best 9 to use an earlier configuration. the error maybe from a virus or hacker. If the system fails during a batch process then the system then the master file may be corrupted. This means that an earlier configuration must be used. Banks will keep many more than 3 generations.
Doing Updates (batch) When transactions are recorded on paper such as one of the old manual transactions using a card then the master file is updated using a batch process when convenient. The process by its nature is always sequential and may still involve magnetic tape. There are two stages to this process: collection/ storage of transaction data in a transaction file, the second stage is updating master file by processing the transaction file. When a batch update is carried out it involves:
retrieving data from tape batch update begins at the start of the tape All the data is restored in the order it was stored 2 batch update finishes when the end of the tape is reached 0 Right: Manual Imprinter: These machines are not very common anymore but if a card is not working properly then one of these might be used. Left: Inside view of the Magstars with 3590 tapes and drives. This is one of the IBM 3590 computers similar to the ones large banks are still using. Bottom Right: Tape cartridge for IBM 3590. This one only saves 10 Gb of data. 3590 E model extended length tape cartridges that can contain up to 120 GB of data (3:1 compression). The tapes are normally in banks so that much larger amounts of data can be stored. Updates in Real-time Real-time processing occurs at that time not at a later stage. In a large system this will mean that a 2 large number of users will be using the system at once. The steps involved in real-time processing 1 involve: sending transaction data to a master file in an online database the empoyee will perform data verification and validation as the transaction is performed (i.e.
asking customer if their details are correct) confirmation of the completion of the transaction will be received and a receipt is handed to customer. Data will be stored using a direct access device i.e. harddrive and not a sequential device such as tape drive 4.4 Other Information Processes All information play a role in TPS' but the HSC focus' on Collecting and analysing 2 Collecting (hardware [MICR, ATM, barcode readers], forms [paper forms, on-screen forms, web 2 forms]) Analysing data (decision support systems, data mining, management Information Systems) Worksheet for 4.4 Other Information Processes Collecting Collecting in TPS systems comes as a result of the generation of data from a transaction. For example when goods are brought by EFTPOS there will be a receipt, when funds are withdrawn 2 from an ATM there will be data collected and a receipt generated. Collecting in a TPS involves 3 hardware such as MICR readers, card readers [for EFTPOS] or maybe ATMs. hardware forms Collecting: Hardware Hardware used to collect data in a TPS include, MICR readers, ATMs and barcode readers MICR (magnetic Ink character recognition) systems are commonly used by banks in reading the account details which
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are located at the bottom of cheques. The ink used to print the characters contain magntic particles. The cheques may be scanned by a teller but will normally be processed as part of a batch much later. Right: This is an MICR reader. There are many on the market
ATM (automatic telling machine) are used by banking customers to withdraw money and do transactions without the necessity of walking into a bank. When people use an ATM they are participants in a real-time system. data is transferred between the ATM and the banks central computer normally using a private leased line. Left: ATM Barcode Readers: Are optical (laser) devices which read barcodes by scanning them with a laser. barcodes will store information about the products on the shelves including product name, product price, they often store an image which will display on a screen, an order code and sometimes other information as well. Collecting: Forms Forms are used to collect data from customers. There are 3 different types of forms we will examine: Paper forms: will normally be processed as a batch. 2 5 On-screen Forms: are created for data entry to a database which will be updated real-time. The computer may be connected through to a database by a network connection or more likely for a TPS, a private leased line. Web Forms: Web forms are much the same as On-screen forms but will be accessed through the internet. Analysing Data The transactions from a TPS are all stored in a database and will be analysed extensively to maximise profits and marketing possibilities. The output of a TPS will become the input for other systems such as: DSS and MIS DSS (decision support systems): 2 Decision Support Systems are created to help people make decisions by providing access to 6 information and analysis tools. many stockbrokers now use programs that will automatically put in requests to sell shares once they reach a certain price (either high or low). A DSS creates a mathematical model of the system which helps decison making about actions affecting a person organisation. Another example of a decision support system is the simple analysis tools that banks use to help formulate loans for prospective customers. A DSS allows the users to pose what-if questions and by changing a number of variables and then find out what the outcomes would be. In the home loan DSS customers can analyse how paying off more each pay would affect their loans, how a different type of loan may make it easier to make ends meet and by so doing tailor
the loan to suit the customer. A DSS depends upon the accuracy of the maths involved in creating the model and the ability of the user to accurately interpret the resulting data. Data Mining is used to find relationships and patterns amongst the data transaction data stored. MIS (Management Information Systems): Management Information Systems provide information to managers of an organisation. This relates to reports, statistics, stock inventories, payroll details, budgets or any other details that assist managers with running an organisation. An EIS, executive Information System is a form of MIS designed for upper management and provides information which might help them make decisions ona strategic level about future directions or issues concerning managers. There are a range of different reports that help managers make predictions and help manage a company including: Scheduled Reports: reports which are generated on a regular basis Forecasting Reports: used to help make predictions about trends On-demand Reports: generated on request to meet specific needs Exception Reports: To report unexpected occurences MIS and EIS are really specialist examples of Decision Support Systems (DSS) 4.5 Issues Related to Transaction Processing Systems Transaction processing systems have made and are making big changes to the way we look for goods and the way they are purchased. ATMs have made it much easier to withdraw money while internet banking has made the process of paying bills and scheduling payments very easy for many people. But what are the downsides? How has this technology affected society overall? For the HSC "Students learn to: 2 assess the impact on participants involved in transaction processing 7 identify jobs that have changed and/or jobs that have been created as a result of transaction processing, and report on the implications of these changes for participants in the system discuss alternatives for when the transaction processing system is not available and explain why they need to be periodically tested identify security, bias and accuracy problems that could arise from the actions of participants" HSC Syllabus p.47
Contents Nature of Work (automation of Jobs, people as Participants) Non-Computer procedures Bias Importance of Data (data security, data accuracy, data integrity) Control in Processing Worksheet for 4.5 Issues Related To Transaction Processing Systems Nature of Work Changes in technology can cause stress and uncertainty for many people. Older people who were raised with computers can find it very stressful being forced into higher and higher levels of computerisation. In areas involved with sales and customer service Transaction processing system have changed the way that people work. There are 2 areas that the HSC is primarily interested in (see HSC Syllabus p 47): 2 8 the automation of jobs once performed by clerks: this impacts in a variety of ways including~ job losses, deskilling of the workforce when their jobs become more tedious and require less skills, reskilling where new skills are required when the job changes the bypassing of clerks by people in the environment performing with, for example collecting, ATM machines: This also impacts in a variety of ways including ~ massive job losses (including tellers at the counters and back office staff), fees imposed on users to discourage them from going to the counter, Customers as participants ands direct users (by completing online forms, online transactions) CASE STUDY: Stamps come unstuck: mail goes online Non-Computer Procedures When computer systems fail companies need non-computer procedures which can come into play. This becomes very important if you have customers who want to buy goods. Companies 2 cannot afford to lose business. Forms need to be used and manual records need to be maintained 9 which will be entered as a batch when the system comes back online. Students need to discuss alternatives for when the transaction processing system is not available and explain why they need to be periodically tested.
Bias Data should be free from bias. data bias refers to bias a one sided distortion of the truth within a 3 data source. The bias maybe intentional where a group such as a government body or 0 organisation is trying to push a point of view or it can be unintentional such as an individuals point of view. data straight from a TPS rarely contains bias because of the nature of the data i.e. cash transactions. However this data can becomes biased as people add comments or when information may be taken out of context and becomes skewed. Importance of Data Data in a TPS has a different significance to many other systems because it is dealing with cash. If data is lost it may have significant financial implications. As such it is critical that businesses have procedures to ensure that data is secure, accurate and that data integrity is maintained. Data Security: data security involves safeguarding the data from malicious or unintentional corruption or theft or data. This corruption may be from hackers, viruses, staff or natural cause such as fire. IT professionals try to ensure data integrity by: Restricting the levels of access by using logins and passwords with varying levels of access depending upon requirements for access to the information stored. Firewalls: to restrict unauthorised access by hackers Virus checks must be carried out on a very regular basis 3 security patches must be current so that any security flaws are not used by hackers or trojans 1 regular backups must be made and stored away from the physical location of the database Data Accuracy: Every effort must be made to ensure that data is accurate. Data validation is used to restrict mistakes on entering mistakes while data verification is carried out to try to pick up errors. Data Integrity: Data integrity describes the overall reliability of the data. Data integrity with real time systems involves the ACID test (atomicity, consistency, isolation, and durability) Atomicity: either all steps in a transaction are completed or the entire transaction is cancelled Consistency: Consistency ensures that only operations that comply with database validity constraints are allowed. For instance, a database tracking a checking account may only allow unique check numbers to exist for each transaction. An operation that repeats a check number should fail due to consistency and ensure that the information in the database is correct and accurate. A network failure or a lack of disk space can also cause consistency problems. Consistency rules enforced by the database will make sure that these situations do not leave
information in an inconsistent state. Isolation: A teller looking up a balance must be isolated from a concurrent transaction involving a withdrawal from the same account. This means that only when the withdrawal transaction is successfully completed will the new balance be reported. Durability: Durability ensures that once a transaction is complete the information as changed will survive failures of the system. A system crash or other failure must not be allowed to lose the contents of the database. Durability is often achieved through separate transaction logs that can "re-create" all transactions from a checkpoint. Other ways include database "mirrors" which replicate the database on another server. Backups by themselves do not provide "durability". 3 Control in Transaction Processing 2 Precautions must be taken to ensure that false or criminal transactions do not take place. HSC Questions on TPS 2002 2003 Question 25 Transaction Processing Systems (20 marks) Use a SEPARATE writing booklet. (a) (i) Define real-time processing, and briefly describe a situation where real-time processing is appropriate. (3 marks) (ii) Describe bias in data collection, and provide an example. (3 marks) Use the following information to answer parts (b) and (c). 3 Quality Fish Farm (QFF) sells fresh f ish to restaurants throughout Australia from its farm in 3 Tasmania. All fish are shipped by express freight in special protective boxes to ensure freshness on arrival. QFF has a transaction processing system (TPS) that processes sales and tracks shipments. This system includes a web-based facility used by restaurants to accept shipments. When a shipment is delivered to a restaurant the chef inspects the shipment for freshness. The chef then accesses QFF s website, logs onto the sales TPS, and enters the shipment number (taken from the box). The system then displays the items of the shipment. The chef accepts or rejects each item. When an item is rejected, the chef is required to enter a reason. The system uses this information to update the restaurant s bill for the shipment. The transaction processing system also allows orders to be entered and bills to be paid online. (b) With reference to the information system diagram on page 19 (included below), describe the following components and their relationship in the context of Quality Fish Farm s information
system: (6 marks) purpose; participants; data/information; information technology; collecting; storing and retri e ving; processing.
(c ) (i ) Describe measures that can assist accurate data entry by the restaurant employees. (3 marks) (ii) Discuss the impact of the use of this information system on the employees of Quality Fish Farm and the restaurants. (5 marks)
2004 Question 25 T ransaction P r ocessing Systems (20 marks) Use a SEPARATE writing booklet. (a) (i) Define data integrity and briefly describe ONE measure that may help to ensure data integrity. (ii) Define datawarehouse and describe its purpose. Use the following information to answer parts (b) (c). One of Australia s largest organisations recently conducted the country s biggest e-voting project, allowing its 2 million members to vote via the internet. Each voter was sent a personal identification number (PIN) by post. The voter logged onto a secure website with his/her membership number and PIN before the voting deadline. The e-voting system checked that the user had completed all voting details correctly according to voting rules. Once the vote was accepted, the voter s details were tagged to prevent multiple voting, and a confirmation was generated for the voter. (b) Describe the e-voting transaction processing system in terms of the information processes of: collecting; storing; processing the tagging of voter details and counting of votes. (c) (i) Outline backup procedures suitable for this e-voting transaction processing system so that no votes will be lost in the event of a system failure.
(ii) Analyse this e- v oting transaction processing system to determine both its strengths and its weaknesses. 2005 (a)(i) Define batch processing and give an example. 3 Marks (a)(ii) Define MICR and give an example of its use. 3 Marks Use the following information to answer parts (b) (c). A cinema allows customers to purchase movie tickets via the internet. Using a web browser, customers select the movie session they wish to see and submit credit card details. The system provides the customer with an image of a ticket which contains a unique bar code. The customer prints the image and brings the hard copy to the cinema. Entry to the movie is via a turnstile
capable of reading that bar code. (b)(i) Design a suitable web-based data entry screen for the customer to submit data about their choice of movie session, and their credit card details. Indicate clearly what screen elements are being used to input the data (eg, text field, pull-down menu, radio buttons), and justify your choices. 4 Marks
(b)(ii) Describe the sequence in which this real-time transaction processing occurs, and identify the main information technology required at each stage. 4 Marks
(c) The cinema company wishes to implement a system where customers can purchase tickets via their mobile phones. The customers send a text message containing the movie session they wish to see. An image of the ticket, with a barcode, is downloaded to the customer s phone. The cost of the ticket is added to their phone bill. At the cinema turnstile, the customer displays the image of the ticket and waves the phone over the barcode reader. Identify and discuss the advantages and disadvantages of the mobile phone system, the webbrowser system, and a conventional system where tickets are bought at the cinema. 6 Marks
4.1 Characteristics of A Transaction Processing System Four important characteristics of a TPS are: Rapid Response 1 Reliability Inflexibility Controlled Processing
Batch Processing Real-time Processing Transaction Processing Monitors Data Validation Manual Transaction Systems Questions for 4.1 Batch Processing Vs Real Time Processing Batch Processing: was developed early on when computers were scarce and computing time was expensive. batch processing reduced costs by reducing the time for user input. In batch processing all the information that needs to be processed is collected and processed as a batch (group) at a later time.
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This machine shown above was used by US Agricultural Department to store statistics on erosion. You can see how all the punch cards are processed together. Real Time Processing: The processing occurs on the spot at that time. Examples of real time processing in TPS systems are EFTPOS machines and ATMs such as is happening in the image. When goods are purchased using EFTPOS the transaction occurs on the spot. 2 main concerns with real-time processing are: concurrency: ensures that more than one user cannot change the same data at
the same time. atomicity: all the steps in a transaction are completed or no transaction takes place and any changes do not go through. HSC Questions Transaction Processing Monitor This is software used to initiate and monitor the transaction inorder to reduce errors and is sometimes referred to as middleware. TP monitor technology controls transaction applications and performs business logic/rules computations and database updates in distributed client server environments. TP monitor technology is used in data management, network access, security systems, delivery order processing, airline reservations, and customer service.
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Data Validation this is the process of checking the accuracy of entered data. This involves software called a transaction processing monitor (TPM) and requires 2 processes: Transaction Initiation: This is like a communications handshake and sets up the protocols and acknowledges the readiness of the system to send and receive the transaction data. This is used to reduce and help eliminate errors. Times are added as headers in the data to allow the data to be traced in the evnt of data loss. 4 Field Checking: This occurs as data is entered into the database to ensure as far as possible that what is entered makes sense. There are a number of different checks made including: range checks, list checks, type checks and a check digit. Range Check: Checks that the data lie within a specified range of values, e.g., the month of a person's date of birth should lie between 1 and 12. Check Digit: Used for numerical data. An extra digit is added to a number which is calculated from the digits. The computer checks this calculation when data are entered, e.g., The ISBN for a book. Type Check: Checks the data type is the correct type such as data entered in a text field is text, numbers in a numerical field.
List Check: used to compare what is entered compared to a set of accepted data (i.e. a list). This list may include the states of Australia, Months of the year, names of capital cities. Data Validation Questions HSC Questions on Validation and Verification Manual Transaction Systems Manual transaction systems are business systems which operate without an information system (i.e. no computers). They have been around for thousands of years. The earliest writings are Sumerian business receipts on clay tablets which are around 5 thousand years old. But of course people still keep manual transaction records. You probably keep receipts for goods that you buy. You may keep these for tax reasons or for warranties but either way they are transaction records. Most people still keep a range of receipts on paper. Until recent times many records were still stored in account books. This required bookkeepers to 5 balance the accounts. These are the manual equivalent of spreadsheets. However these days most companies are electronic whether it be buying a seat on a plane or purchasing a book. Transferring these paper based records into an electronic system has many benefits including: customers can purchase goods at their convenience it is easy to do stocktakes reduced wage costs Whatever the peripheral benefits computerisation of a manual system will aim to maximise profits. 4.2 Examples of Transaction Processing Systems In this section we will look at components of a TPS and some real life examples. 6 Contents Components of a TPS Examples of Real-time Transaction Processing (reservation systems, POS, Library Loans)
Examples of Batch Transaction Processing
Questions for 4.2 Characteristics of a TPS Components of a TPS The components of a TPS include hardware, software and people. The most important component of a TPS are people. Without people the system does not have customers and without customers it does not have a funtion to perform. People in a TPS can be divided into 3 categories: users, participants and people from the environment. Users: The users are people employees of the company who own the TPS. They will use it to provide information information about the system but will not enter data themselves. The 7 information they provide from the TPS may be used to provide inputs for other information systems such as stock control, marketing etc... Participants: Participants are direct users of the system. These are the people who will enter the data. They include data entry operators, customer service operators, people working at checkouts and anyone carrying out the tasks required to process the data. People From The Environment: These are people who do not directly work for the company but people off the street who sometimes require the services of a TPS as they enter transactions and validate data such as a customer withdrawing money from an ATM. Examples of Real-time Transaction Processing There are 3 examples of TPS examined in the HSC:reservation systems, POS, Library Loans Reservation Systems These are used by businesses where services need to be booked. Examples of reservation systems can be found at travel agencies, airline companies, rental companies, entertainment agencies such as Tickatek or the relevant venues. Every time a booking is made the available resources need to be reduced by the same number or resources reserved or paid for. Once the transaction has 8 taken place then tickets need to be printed credits will be transferred from the customer's account to the booking agency, receipts need to be printed and transaction records need to be updated in the database. Point of Sale (POS) POS is the system that is in place for purchases involving EFTPOS (electronic funds transfer at point of sale). POS is just an abbreviation of the full name of EFTPOS. POS systems are found in many businesses now from major outlets such as Coles or Woolworths to many mixed businesses and petrol stations. The POS system is what allows the convenience of an ATM at midnight. When a transaction takes place, goods are scanned from barcodes or details are typed in, any required
credit card checks are made, a receipt is sent to the customer (displayed on the screen or printed on a receipt), coded inventory data is sent through to update the database and the inventory or bank balance is updated. It will also work out the change required and any receipt will normally itemise items. Library Loans The borrower will normally have a library membership card which will be scanned and checked for overdue books and fines, the borrowed items will be scanned and each item will then be placed under the borrowers name. The details about available books will then be updated on the database. The system will also allow reservations to be placed on the books. Examples of Batch Transaction Processing Contents Cheque Clearance Generation of Bills Credit Card Transactions There are three examples that the NSW HSC syllabus refers to: cheque clearance, bill generation and credit card sales transactions "examples of batch processing, including: clearing of presented cheques 9 generation of bills systems that appear real time, computerising transactions as they occur, but actual updating is processed in batch, such as credit card transactions" HSC syllabus page 45 Clearing of Presented Cheques (Cheque Clearance) Once a cheque is presented to a bank it is normally put to the side and processed as part of a batch. In fact the cheque will become a part of one batch once it is deposited at the bank and then part of another batch once it is sent to the issuer's bank. Each step has built in delays to ensure that people are not paid twice or the money taken out of an account which does not have the money. These days, will electronic processeing cheques are normally cleared within three days it use to take over a week. Generation of Bills
Bills are not pleasant. For many people it always seems that many bills appear at once. This is not coincidence but you will be glad to know that it is not part of some evil plot. Most bills are generated for a fixed time period which the computers will automatically generate once that period has fallen due. Once there is an overlap of bills they will continue to come at the same time because that is how they are generated: as a batch for a fixed time period. The bills are generated as a batch to reduce mailing and printing costs. Some companies will even allow users to view their bills and account details online. Credit Card Transactions Credit card transactions on the internet are very unusual because they appear real time but in fact are actually batch. Huh? Seems strange doesn't it. But in reality the only real time transaction is the check that is made to ensure that the card is current, and is not listed as lost, stolen, cancelled or over the limit. The transaction i8s actually processed as a batch at a later stage. Of course there are still manual credit card transactions which are entered into the TPS. these transactions may take from hours to weeks before they are processed. The manual aspects to online credit card transactions bring in issues of security (credit card fraud, identity theft), privacy (personal details can be read) and ethical issues.
Case Study Students create their own virtual case studies including feasibility studies, and presentation to virtual executives of organisation. sample PowerPoint for a case study 1 0 Laura's Liquorland TPS notes from Andrew Rebecca TPS PowerPoint Celia PowerPoint 4.3 Storing and Retrieving many people daily rely on the reliability of TPS and as such they must have an efficient and safe 1 method of storage and retrieval. Databases are 1 used to store the data and requires a safe and effective plan for backups and recovery if anything goes wrong.
Contents Databases and files (hierarchical, network or relational structure, Good Design) Data warehousing Backup Procedures Doing Updates (batch) Real-time Updates Worksheet for 4.3 Storing and Retrieving Databases and Files hierarchical, network relational structure Good Design For TPS Files and TPS' 1 2 A database is an organised collection of data. When an organisation stores its operational records and accounts in a databses this type of database is then called an operational database. The database is organised in a schema. The TPS will out of necessity have access to aspects of the database such as accounts and stock. Because the TPS only has access to a subset of the database this is called a subschema. There are 3 different types of schemas which may be used to organise the database structure; hierarchical, network or relational structure. Hierarchical Databases: are organised in a hierarchical or tree like structure consisting of nodes and branches. Each node can have many branches but the child node can only have one parent node.
Network Database: In networked databases the primary node in a branch is called the owner (parent) of that group with information relevant to that topic being a member of that level 0 node. The child nodes can be linked (member) of other groups.
Relational Databases: A relational database organises information through a series of related tables. Realtionships are formed between tables to link various types of information. Relational databases are the most commonly used type of database. A relational database consists of a
collection of tables that store particular sets of data. The invention of the relational database system has standardized the way that data is stored and processed. Most of the database management systems used today are based on the relational system.
Good Design For a TPS A good TPS must have several important characteristics: Good Data Placement: Commonly used blocks of data should be together to speed up data access rates. Short Transactions: Break up complicated and long transactions into shorter transactions to 1 improve processing time and concurrency. 3 High Normalisation: A high level of normalisation (reduction of redundant data) increases access rates, time taken for updates and concurrency for a database Archiving of Historical Data: Old data needs to be archived to reduce the overall physical size of the database which increases access (including queries and reports) and backup times. Good Hardware Configuration: The hardware should be physically capable of dealing with the demands placed upon it including enough physical space to store the data. Data Warehousing consolidated subject-oriented 1 4 historical read only Data is a valuable commodity which is traded and sold. This data ranges from personal information on customers, demographics on customer bases for products, sales figures and so on. All of this data is stored in databases called data warehouses. This data can then be used for a
myriad of reasons. Reports can be writtenn or marketing plans may revised all based on figures stored in a data awarehouse. AI programs are often used to look for meaningful patterns. people who look after these data warehouses are called Knowledge Managers. Data stored in data warehouses is used to look for patterns in credit card usage which points to fraud. Refer also to knowledge management , financial systems , data mining , Expert Systems A data warehouse provides data that is consolidated, subject-oriented, historical and read only Consolidated: data is organised in a consistent manner to allow usage of the data across organisations. Subject oriented: data is stored by subject to allow querying and reports. Historical: data is stored over a long time period. A longer time frame allows better analysis of the data. Read-Only: The data can not be changed by users. It can only be added to. HSC Questions on Data Warehousing Files and TPS' A file is a stored block of data. In a database a file is a set of related facts such as the details about on customer or the details about a particular loan, particular product etc... batch processing and real-time processing require different types of files and different ways to store and retrieve the information. TPS' have five different file types: Master File: This is the main copy of a database and is the main operational database for the TPS. A copy of transaction data must be stored in this file. 1 5 Transaction Files: This is a collection of the transaction records. This is used to update the transactions stored on the master file. Audirors will use these files to audit a companies transaction records. A Report File: A collection of data that has been formatted ready to print and present Work File: temporary file created during a transaction A program File: Contains code for the processing of data> This may be in SQL or another programming language. Backup Procedures Organisations using TPS are very dependent on the reliability of their systems. As such backup 1 procedures must be well planned and recovery procedures must have a minimal disruption to the 6 organisation Contents
Recovery Process Forward and Backward Recovery 3 Generations of Backups (grandfather, father Son) Partial backups Updating In A Batch Updating In real-time Recovery Process A TPS may crash or have errors for any number of reasons including: hardware failure, software failure, human error (such as entering the wrong data), viruses and worms or external problems such as power failure/ natural disaster such as flood. In order to deal with the failures the TPS must be able to restore correct data where possible. The recovery process is the process by which the database is restored back to a reliable configuration. The recovery process includes: Backups: A copy of the database is made on an ongoing basis. usually at least once a day when system is not used a backup of the entire system will be made. Journal: Journals record what happens in a database. There are two types of journals: transaction 1 logs which will record all the details about a transaction. Because a TPS is all about transactions a 7 transaction log will be long and detailed. Most of the time a transaction can be pined down to a rough time and then tracked from there. The journal roll from the register will form a hard copy of what is recorded. The second type is the database change log which shows changes made to the database. Remember most details in the database will not change very often. Checkpoint: Periodically throughout the day any information system will create checkpoints. All processing will very temporarily stop while all parts of the system are synchronised. When failures in a TPS occur the system can be restored back to the last checkpoint or any other checkpoint chosen. as such checkpoints should be very regular, at least several times an hour. Processing can then be resumed from the last checkpoint. Recovery Manager: This is a program used to restore the database back to the chosen checkpoint. Forward and Backward Recovery There are two types of recovery procedures: backward recovery and forward recovery. 1 8 Backward Recovery: is used like an UNDO Button for a TPS. With a backward recovery the database administrator will try to undo unwanted changes. Forward Recovery: is like a REDO button where lost transactions are covered from the trasnaction
journal and the backup. 3 Generations of Backups (Grandfather-Father-Son) Grandfather-father-son is a backup system where 3 generations (backups made over 3 differnt times) where the grandfather is the oldest and the son is the most recent backup. The phrase is a general one and many more than 3 generations may be saved. Sometimes the most recent backup 1 is not the one we want. It maybe that for some reason an error crept into the system and it is best 9 to use an earlier configuration. the error maybe from a virus or hacker. If the system fails during a batch process then the system then the master file may be corrupted. This means that an earlier configuration must be used. Banks will keep many more than 3 generations.
Doing Updates (batch) When transactions are recorded on paper such as one of the old manual transactions using a card then the master file is updated using a batch process when convenient. The process by its nature is always sequential and may still involve magnetic tape. There are two stages to this process: collection/ storage of transaction data in a transaction file, the second stage is updating master file by processing the transaction file. When a batch update is carried out it involves:
retrieving data from tape batch update begins at the start of the tape All the data is restored in the order it was stored 2 batch update finishes when the end of the tape is reached 0 Right: Manual Imprinter: These machines are not very common anymore but if a card is not working properly then one of these might be used. Left: Inside view of the Magstars with 3590 tapes and drives. This is one of the IBM 3590 computers similar to the ones large banks are still using. Bottom Right: Tape cartridge for IBM 3590. This one only saves 10 Gb of data. 3590 E model extended length tape cartridges that can contain up to 120 GB of data (3:1 compression). The tapes are normally in banks so that much larger amounts of data can be stored. Updates in Real-time Real-time processing occurs at that time not at a later stage. In a large system this will mean that a 2 large number of users will be using the system at once. The steps involved in real-time processing 1 involve: sending transaction data to a master file in an online database the empoyee will perform data verification and validation as the transaction is performed (i.e.
asking customer if their details are correct) confirmation of the completion of the transaction will be received and a receipt is handed to customer. Data will be stored using a direct access device i.e. harddrive and not a sequential device such as tape drive 4.4 Other Information Processes All information play a role in TPS' but the HSC focus' on Collecting and analysing 2 Collecting (hardware [MICR, ATM, barcode readers], forms [paper forms, on-screen forms, web 2 forms]) Analysing data (decision support systems, data mining, management Information Systems) Worksheet for 4.4 Other Information Processes Collecting Collecting in TPS systems comes as a result of the generation of data from a transaction. For example when goods are brought by EFTPOS there will be a receipt, when funds are withdrawn 2 from an ATM there will be data collected and a receipt generated. Collecting in a TPS involves 3 hardware such as MICR readers, card readers [for EFTPOS] or maybe ATMs. hardware forms Collecting: Hardware Hardware used to collect data in a TPS include, MICR readers, ATMs and barcode readers MICR (magnetic Ink character recognition) systems are commonly used by banks in reading the account details which
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are located at the bottom of cheques. The ink used to print the characters contain magntic particles. The cheques may be scanned by a teller but will normally be processed as part of a batch much later. Right: This is an MICR reader. There are many on the market
ATM (automatic telling machine) are used by banking customers to withdraw money and do transactions without the necessity of walking into a bank. When people use an ATM they are participants in a real-time system. data is transferred between the ATM and the banks central computer normally using a private leased line. Left: ATM Barcode Readers: Are optical (laser) devices which read barcodes by scanning them with a laser. barcodes will store information about the products on the shelves including product name, product price, they often store an image which will display on a screen, an order code and sometimes other information as well. Collecting: Forms Forms are used to collect data from customers. There are 3 different types of forms we will examine: Paper forms: will normally be processed as a batch. 2 5 On-screen Forms: are created for data entry to a database which will be updated real-time. The computer may be connected through to a database by a network connection or more likely for a TPS, a private leased line. Web Forms: Web forms are much the same as On-screen forms but will be accessed through the internet. Analysing Data The transactions from a TPS are all stored in a database and will be analysed extensively to maximise profits and marketing possibilities. The output of a TPS will become the input for other systems such as: DSS and MIS DSS (decision support systems): 2 Decision Support Systems are created to help people make decisions by providing access to 6 information and analysis tools. many stockbrokers now use programs that will automatically put in requests to sell shares once they reach a certain price (either high or low). A DSS creates a mathematical model of the system which helps decison making about actions affecting a person organisation. Another example of a decision support system is the simple analysis tools that banks use to help formulate loans for prospective customers. A DSS allows the users to pose what-if questions and by changing a number of variables and then find out what the outcomes would be. In the home loan DSS customers can analyse how paying off more each pay would affect their loans, how a different type of loan may make it easier to make ends meet and by so doing tailor
the loan to suit the customer. A DSS depends upon the accuracy of the maths involved in creating the model and the ability of the user to accurately interpret the resulting data. Data Mining is used to find relationships and patterns amongst the data transaction data stored. MIS (Management Information Systems): Management Information Systems provide information to managers of an organisation. This relates to reports, statistics, stock inventories, payroll details, budgets or any other details that assist managers with running an organisation. An EIS, executive Information System is a form of MIS designed for upper management and provides information which might help them make decisions ona strategic level about future directions or issues concerning managers. There are a range of different reports that help managers make predictions and help manage a company including: Scheduled Reports: reports which are generated on a regular basis Forecasting Reports: used to help make predictions about trends On-demand Reports: generated on request to meet specific needs Exception Reports: To report unexpected occurences MIS and EIS are really specialist examples of Decision Support Systems (DSS) 4.5 Issues Related to Transaction Processing Systems Transaction processing systems have made and are making big changes to the way we look for goods and the way they are purchased. ATMs have made it much easier to withdraw money while internet banking has made the process of paying bills and scheduling payments very easy for many people. But what are the downsides? How has this technology affected society overall? For the HSC "Students learn to: 2 assess the impact on participants involved in transaction processing 7 identify jobs that have changed and/or jobs that have been created as a result of transaction processing, and report on the implications of these changes for participants in the system discuss alternatives for when the transaction processing system is not available and explain why they need to be periodically tested identify security, bias and accuracy problems that could arise from the actions of participants" HSC Syllabus p.47
Contents Nature of Work (automation of Jobs, people as Participants) Non-Computer procedures Bias Importance of Data (data security, data accuracy, data integrity) Control in Processing Worksheet for 4.5 Issues Related To Transaction Processing Systems Nature of Work Changes in technology can cause stress and uncertainty for many people. Older people who were raised with computers can find it very stressful being forced into higher and higher levels of computerisation. In areas involved with sales and customer service Transaction processing system have changed the way that people work. There are 2 areas that the HSC is primarily interested in (see HSC Syllabus p 47): 2 8 the automation of jobs once performed by clerks: this impacts in a variety of ways including~ job losses, deskilling of the workforce when their jobs become more tedious and require less skills, reskilling where new skills are required when the job changes the bypassing of clerks by people in the environment performing with, for example collecting, ATM machines: This also impacts in a variety of ways including ~ massive job losses (including tellers at the counters and back office staff), fees imposed on users to discourage them from going to the counter, Customers as participants ands direct users (by completing online forms, online transactions) CASE STUDY: Stamps come unstuck: mail goes online Non-Computer Procedures When computer systems fail companies need non-computer procedures which can come into play. This becomes very important if you have customers who want to buy goods. Companies 2 cannot afford to lose business. Forms need to be used and manual records need to be maintained 9 which will be entered as a batch when the system comes back online. Students need to discuss alternatives for when the transaction processing system is not available and explain why they need to be periodically tested.
Bias Data should be free from bias. data bias refers to bias a one sided distortion of the truth within a 3 data source. The bias maybe intentional where a group such as a government body or 0 organisation is trying to push a point of view or it can be unintentional such as an individuals point of view. data straight from a TPS rarely contains bias because of the nature of the data i.e. cash transactions. However this data can becomes biased as people add comments or when information may be taken out of context and becomes skewed. Importance of Data Data in a TPS has a different significance to many other systems because it is dealing with cash. If data is lost it may have significant financial implications. As such it is critical that businesses have procedures to ensure that data is secure, accurate and that data integrity is maintained. Data Security: data security involves safeguarding the data from malicious or unintentional corruption or theft or data. This corruption may be from hackers, viruses, staff or natural cause such as fire. IT professionals try to ensure data integrity by: Restricting the levels of access by using logins and passwords with varying levels of access depending upon requirements for access to the information stored. Firewalls: to restrict unauthorised access by hackers Virus checks must be carried out on a very regular basis 3 security patches must be current so that any security flaws are not used by hackers or trojans 1 regular backups must be made and stored away from the physical location of the database Data Accuracy: Every effort must be made to ensure that data is accurate. Data validation is used to restrict mistakes on entering mistakes while data verification is carried out to try to pick up errors. Data Integrity: Data integrity describes the overall reliability of the data. Data integrity with real time systems involves the ACID test (atomicity, consistency, isolation, and durability) Atomicity: either all steps in a transaction are completed or the entire transaction is cancelled Consistency: Consistency ensures that only operations that comply with database validity constraints are allowed. For instance, a database tracking a checking account may only allow unique check numbers to exist for each transaction. An operation that repeats a check number should fail due to consistency and ensure that the information in the database is correct and accurate. A network failure or a lack of disk space can also cause consistency problems. Consistency rules enforced by the database will make sure that these situations do not leave
information in an inconsistent state. Isolation: A teller looking up a balance must be isolated from a concurrent transaction involving a withdrawal from the same account. This means that only when the withdrawal transaction is successfully completed will the new balance be reported. Durability: Durability ensures that once a transaction is complete the information as changed will survive failures of the system. A system crash or other failure must not be allowed to lose the contents of the database. Durability is often achieved through separate transaction logs that can "re-create" all transactions from a checkpoint. Other ways include database "mirrors" which replicate the database on another server. Backups by themselves do not provide "durability". 3 Control in Transaction Processing 2 Precautions must be taken to ensure that false or criminal transactions do not take place. HSC Questions on TPS 2002 2003 Question 25 Transaction Processing Systems (20 marks) Use a SEPARATE writing booklet. (a) (i) Define real-time processing, and briefly describe a situation where real-time processing is appropriate. (3 marks) (ii) Describe bias in data collection, and provide an example. (3 marks) Use the following information to answer parts (b) and (c). 3 Quality Fish Farm (QFF) sells fresh f ish to restaurants throughout Australia from its farm in 3 Tasmania. All fish are shipped by express freight in special protective boxes to ensure freshness on arrival. QFF has a transaction processing system (TPS) that processes sales and tracks shipments. This system includes a web-based facility used by restaurants to accept shipments. When a shipment is delivered to a restaurant the chef inspects the shipment for freshness. The chef then accesses QFF s website, logs onto the sales TPS, and enters the shipment number (taken from the box). The system then displays the items of the shipment. The chef accepts or rejects each item. When an item is rejected, the chef is required to enter a reason. The system uses this information to update the restaurant s bill for the shipment. The transaction processing system also allows orders to be entered and bills to be paid online. (b) With reference to the information system diagram on page 19 (included below), describe the following components and their relationship in the context of Quality Fish Farm s information
system: (6 marks) purpose; participants; data/information; information technology; collecting; storing and retri e ving; processing.
(c ) (i ) Describe measures that can assist accurate data entry by the restaurant employees. (3 marks) (ii) Discuss the impact of the use of this information system on the employees of Quality Fish Farm and the restaurants. (5 marks)
2004 Question 25 T ransaction P r ocessing Systems (20 marks) Use a SEPARATE writing booklet. (a) (i) Define data integrity and briefly describe ONE measure that may help to ensure data integrity. (ii) Define datawarehouse and describe its purpose. Use the following information to answer parts (b) (c). One of Australia s largest organisations recently conducted the country s biggest e-voting project, allowing its 2 million members to vote via the internet. Each voter was sent a personal identification number (PIN) by post. The voter logged onto a secure website with his/her membership number and PIN before the voting deadline. The e-voting system checked that the user had completed all voting details correctly according to voting rules. Once the vote was accepted, the voter s details were tagged to prevent multiple voting, and a confirmation was generated for the voter. (b) Describe the e-voting transaction processing system in terms of the information processes of: collecting; storing; processing the tagging of voter details and counting of votes. (c) (i) Outline backup procedures suitable for this e-voting transaction processing system so that no votes will be lost in the event of a system failure.
(ii) Analyse this e- v oting transaction processing system to determine both its strengths and its weaknesses. 2005 (a)(i) Define batch processing and give an example. 3 Marks (a)(ii) Define MICR and give an example of its use. 3 Marks Use the following information to answer parts (b) (c). A cinema allows customers to purchase movie tickets via the internet. Using a web browser, customers select the movie session they wish to see and submit credit card details. The system provides the customer with an image of a ticket which contains a unique bar code. The customer prints the image and brings the hard copy to the cinema. Entry to the movie is via a turnstile
capable of reading that bar code. (b)(i) Design a suitable web-based data entry screen for the customer to submit data about their choice of movie session, and their credit card details. Indicate clearly what screen elements are being used to input the data (eg, text field, pull-down menu, radio buttons), and justify your choices. 4 Marks
(b)(ii) Describe the sequence in which this real-time transaction processing occurs, and identify the main information technology required at each stage. 4 Marks
(c) The cinema company wishes to implement a system where customers can purchase tickets via their mobile phones. The customers send a text message containing the movie session they wish to see. An image of the ticket, with a barcode, is downloaded to the customer s phone. The cost of the ticket is added to their phone bill. At the cinema turnstile, the customer displays the image of the ticket and waves the phone over the barcode reader. Identify and discuss the advantages and disadvantages of the mobile phone system, the webbrowser system, and a conventional system where tickets are bought at the cinema. 6 Marks
