INFO3/4
- Created by: Wole Bello
- Created on: 29-11-12 19:04
Topic 1
Emerging Technologies; technologies in the process of development that will likely shape the future
Mobile Working:method of working; employee works from home instant from the office
Bluetooth:A standaing for sending data using short-range radio signals, e.g. Teenagers sending photos/music by mobile phone
devices using this tool: Printers, digital cameras,laptop, mobile phone wireless headset for calls
Blackberry: A PDA(Personal Digital Assitant) Multiple uses; calling- recieving & out-going, Email,Internet,text messaging
Mobile Phones:calls;out-going and recieved, texting, music player, browsing on the internet
Nanotechnology:Scientific technology:not made yet set to transform lives. Nanometre 1/100,000 thickness of a human hair future use: Printable electronic circuits, personnel computers with the power of today's computer centres.
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Robotics: Created for chores; lawn,guttters,vaccum,swimming pool Military- bomb disarment
Biotechnology:Biology technology- genetics molecular biology, cell bioology into use forms of ICT
Potential Ict usage
Wireless Energy: constant recharge limited time without charging. Witricity - wireless electricty charger
Novel User interface- Mobile small keyboard but Iphone touch screen meaning screen size is large taking space occupied by keyboard
Flexible screen:Milimetres thick and light. Making it easy to fold up/roll up. Use small amount of energy; original power last long means it good for the environment less recharging
WEB 2.0: acces to video, listen to radio due to highly improved data transmission speed. High speed internet access.
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Smart cars:microships installed in cars to prevent accidents from happen due to human errors in traffic system
DNA- National database: purpose to prevent crime; make arrest offernders in jail, help offices in their investigations. Samples of DNA are taken and used in investigations and stored. Problems: Privacy: not everyone is a crinimal so not everyone' DNA should be stored, police have different opinion
Face recognition: uninsured drivers not on database DLVA, harder to find if license plate is put on the system & identify passengers. Existed system helps to find documents if a car is uninsured or is
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Problems with future ict
Social
Health: a rise in obesity, too much tim on devices and machines e.g. Game consoles & DVD player
routine: less leisure time: less TV watching more internet time
Stress: people anxious,annoyed with learning new stuff with ICT systems; viruses,program crashes
Cultural
Music: buy/listen; normally go to store noow illegally majority of users download or buy from external services e.g.itunes
Social networking & TV: replacing physical interaction communcation is now online(linked to obesity) avaiable programmes allow public to watch whenever it's convenient e.g. BBC iplayer
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Environmental
Increase of carbon footprint by increase use of ICT
Toner/ink cartidge=now refill instead of thrown away and buy new one
Telecommuting; employees working at home= decreasing congestion & C02
Ethical
Personal time: use organisation resources for personal use e.g. emails
Monitor: organisation monitor employees use of internet
Help forums - students in colleges/Universities buy essays on topics + subjects online = cheating
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Technical
Size of computer- microprocessors small size = portable devices
User System Interface: People want ability to communicate with computer Difficult with accuracy of speech recognition e.g.Iphione 4; don't understand Scottish accent
Battery life; devices need constant recharging= intro mircoships use litle power e.g. laptops run longer without use main power
Legal
Privacy: Britain toomuch technology feel like Big Brother- Heathrow T5 idea, identify passengers using finger printing= turns out illegal to do so
Internet: Unathorised permission to use wifi networks= access internet hacker use bandwidth divided amingst users.
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Economic
Workforce:New generation built around ICT so need ICTsystem
R&D:Companies invest in new development take risk= possible outcome compete in area of expertise
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Implications; Problems in society and potential abuse of technology
more dependence on ICT; workers uasge of ICT
Development of machines for common use:Robotics-cleaning devices e.g. lawn mower
improvement in health dept: database holding more key information & ICT controlled scanners prevent illness
Video 'happy slapping' posted on socil networking sites e.g. YouTube promoting cyber-bullying
Identify theft: High risk; credit/debit cards transactions online, shady retailer websites
Illegal sharing of copyright materials e.g. music/films
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Impacts on Organisations
Fast response time; goods relationship with suppliers services on internet; Customer buy goods at any time of day
Remote working possible staff working from home
Policies: Organisations introduce IT polices to reduce chances of misuse of ICT system by employees
Conflicts for WORKERS/CONSUMERS
Work/Play: might not be enough constraint
Constant updates; skills
Work;less family time caused by addition work, meetings
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- Work force
Increase of ICT=organisation compete globally and react to customers request. Majority of services-24/7:part/full time during normal work hours & outside working hours, e.g. mother with children will benefit them
- Procedures
Staff encounter more responbilities plus wider variety of tasks e.g. involved with customer services instead od admin work=Time avaiable to devote more profitable activities for company.
- Ways of foing things in Organisation
System analyst think of best way to fit ICT system(new) around task preformance. Constant charge can stress staff but consulted can lead to tasks being done well. Must obey code of conduct; does & can'ts
Topic 2
Multiple systems have multiple tasks in Organisations
commerical;buy/supply goods to customers
Industrial;manufacture procedures/process raw materails in construction e.g. house builders
Public services; provide goods/service from public funds(taxes) aim: maximum benefit the public
Scale of Organisations
Small:1>50 staff structure:informal network:LANS
Medium:50>500 staff structure:formal network:WANS+LANS
Large:500> staff structure:hiearchical network:WANS+LANS
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Style
Autocratic: Senior managers make decision= workers given instructions. Information channeled upwards= top of chain make decisions. Effective but staff demotivated not as involved as like to be.
Paternalstic:Senior managers cared about employees needs then business. Management decision explain to employees making them happy leading them to be loyal to bosses
Democratic All Staff involved in decision=making process good- everyone commitment bad - everyone's fault. Help in a ICT projects=personnel area of expertise in different field. DMP- doen through a series of meetings.
Laissez faire:Style informal:Company expected to manage itself without assistance from external service. Suits in Partnership of Accountants,Solicator. Method=little communication between staff=probs-lack of leadership
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Ordering Sytem: take customer' order and process payment to company from payer resulting in goods delivered to customers.
Functions:*Send brought goods to customer *Products:make sure it's in stock * products out of stock *Returns of fault goods *refunds to the payer * Payement for the googs; bank details
Additional branch: Customer support; provide additional services for customer who have brought goods/services from organisation e.g. *Complaints *Opening of a new accountants * Transfer of money between between accountants
Manuacture of products deals with:*Customers' complains *Techincal advice given *Issue with payment Refunds under(warrant) gurantee - schedule
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Levels
Stragetic:Task completed from top of 'food' chain e.g. Directors, Headteachers
High level informatino needed
Tactical:Achieve task from directors e.g. Dept heads
reports;summaraise day to day events
Operational:routine day to day tasks e.g. lectures, sale staff, teachers
involved with information everyday e.g. Sainsbury
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different personnel have differnet information neneds for tasks
Suppliers: Supply goods+ Services to Customers
e.g. utility(water,gas,electricty,telephone), Book supplies, maintenace
Close relationship between the two= maxmise profit going both ways
Customers ; people buy goods from Suppliers/Business e.g. large retaielr - pu8rchase paid automatically orders orders automatically- Batch/Bulk
Can be indivdiuals
supply information to companies e.g. Personal info on online payment. Kept later on to promote goods that might interest them. Legalisations in place that must be obligate to.
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Vechile: All vechiles brought,sold, destroyed sent to insurance companies e.g. DVLA.
Tax: Organisation must pay taxes to H.M Revnue & Customs.
Accountant:Company's end of year accountants must be send to companies house.
Organisations exchanging information with external bodies. Argeement made between customers,suplliers & offical bodies how info is to be exchanged. Comapnies- send info to help & expand ICt systemms. Some have same system.
PRIVACY: methods of protection: encrypotion, passwords,private channels,private networks to ensure privacy of personall details
SECURITY:Must not fall into the wrong hands. Ict policy might be in place to ensure this from happening.
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legal implication:
DPA: Protect data sbject(living humans)
- Must not break any law when transferring info- copyright infringement
- Register the use of personal data with info Comminsoner Officer; they handle the data
- Security: sufficent when exchanging personal data
ICT in Organisations
In recent years companies/organisations have used ICT system perform tasks and activities. The aim of this is to improve work performance & business effective. In the following way
Improving productivity of staff *Improving the efficieny with allocated resources Reduce of wastage= low percent of goods stolen by tracking goods *Electonic transfer(£) between partner=increse of profitability of both the supplier and customers
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Accountants: Monitor income & outcome of the business(£), all dept will be linked to this important part of business
Payroll: Paying employees their salaries:some have terms; annual or weekly, this will also include deduction e.g. taxes, From salary £ is taken into other organisation: pension, H.M revenue, Trade Union, EFT(Electronic funds transaction) & BACS used to complete tranasctions.
Personnel: Human Resources contain all employees personal information & work information(WI): training records kept to know strengths & weakness + who needs training.
Supply chain(SC): Process from an order good being supplied to the bad customer. Comapnies rely on each other because they involved i the cycle; producing products & supplying it to their customers. In the process ICT systems are used for management of the system & human resources,stock,other resources
Ideal SC: satisfy customer order without holding stock: impossible to do.
Topic 2
Types of ICT system
Legacy sytem(Old/Current)
New system replacing (masjority of parts) the legacy system. Certain aspewcts will need to be check data portability, transfer of data, Installation of the new system.
Back office:ICt system that run the company but not seen to the general public
*Payroll,accountants,human resources *Telephone & Network management system
Transaction processing: Individual transaction can be carried out (more than person at a time) *Buying a therate ticket * Withdraw money from ATM
Workflow:Manage the operations , activities & resources used in an organisation. Track progess: Items through manufacturing process & Books/Magazines; Quality Check at each stage.
Topic 2
DMS(Document Management Systems): Storing/Archieving sereval documents. *Authorise to share their documents with a wider group over a secure network;privacy & web based DMS- author book out a file + it's version is when updated wehen system is backing up.
MIS ( Management Information systems): Produce information from internal/external sources of data. * Data summarise from other systems in the organisatiosn * Provide information which asist stragetic level staff in the decision making process
Enterprise:Used by large Organisations. * Intergated & co-ordinate business processers * Handle large volumes of data efficently
DSS(Desicion Support System):Assist decision making process with quality info legal implications *Company cannot deny responsibility for an error because "The computer got it wrong"
E-commerce System: Buying/selling aspects of goods/services to customers and clients
Topic 2
DMS(Document Management Systems): Storing/Archieving sereval documents. *Authorise to share their documents with a wider group over a secure network;privacy & web based DMS- author book out a file + it's version is when updated wehen system is backing up.
MIS ( Management Information systems): Produce information from internal/external sources of data. * Data summarise from other systems in the organisatiosn * Provide information which asist stragetic level staff in the decision making process
Enterprise:Used by large Organisations. * Intergated & co-ordinate business processers * Handle large volumes of data efficently
DSS(Desicion Support System):Assist decision making process with quality info legal implications *Company cannot deny responsibility for an error because "The computer got it wrong"
E-commerce System: Buying/selling aspects of goods/services to customers and clients
Topic 3
Differences between the running of a big and a small organisation: Big - one role Small - flexible role=more jobs/tasks
Size of organisation determine formailty
Big - autocratic hierarchical structure Small - democratic
ICT stragety: layout of the business goals with the assist of ICT systems- long/short term objectives
ICT policies in organisation to protect the company and employees from mistakes and errors
Security; ensure law,security of ICT systems and data prevent misuse of its systems
Procurement ressurance/insurance of buying ICT equipment from external providers = good quality value for £ equipment and goods from suppliers
Topic 3
Training: help maximise, improve work performance of staff in the companies
CIO(stragetic level) responsible for ICT strageticc decisions. They have many responsibilities
Topic 4
Stragety are to help reach the organisations or aims,factors that decide an ICT stragety:
Business goals: the company's short/long terms plans for the future
Financial budget:How much is the company willing to spend on the new ICT system
Legacy System: Will the new system be replacing the old system entirely or will the legacy system have some features install on the new system.
Geography of clients:Locations of clients/customers determines the use of the ICt system in how it will end information to them; the more clients the more complexity the system will be.
Legalisation: The sysyerm will have to follow the laws set in place; DPA CMA CDPA
Storage of information:business keep information for long periods of time(backup=insurance)
Topic 4
Large Organisations
ICT; benefits out of new developments for the company
Factors
Software:Upgrade on a regualr basis= improved functionally. Too much change= affect staff work performance
Hardware:Common to be unreliable & maintenance= cost company money= replacement at one stage
Computer:maintenance contracts annually made between producers+organisations. Cost- several hunderds of thousands £
topic 4
Future proofing:ORganisations seeing if the new development can cope with increasing demand of the business in the future. Try to forsee potential development features;*Higher processing power=more apps running at the same time *Data=manipulated in database programmes=mulitple apps can use data
Development:Need to the tech to work to get market advantage ahead of comptetors Ict stragety-flexible in the light of new development
Procurement: Setting up contracts; research external providers of hardware,software+services= choosing external provider from revelant findings from research=value for £
TECH LIFE CYCLE;1R+D:New system invesitagted + then built(cost of hard/software)2 Ascent;Ascent:Money is recovered from the budget 3Matunity;e system is at peak=quality info savings for the company 4Decline;technology is out-of-date time to pack it up+ put £ into replacement
topic 4
Info management: Avaialble to all who needs it - tasks activities, System allow the production of management information
People considerations: New staff,training, Reorganisation:new system in place
Topic 5
ICT policies;staff adapt sensible responbility of their action whenever using an ICT within the organsiation.
Security:Prevent staff from misuse and external/internal threat to the sytem; Legisaltion-DPA CMU CPDA *Passwords/Username;passwords confidental mixture of letters/numbers *not to be shared *If logged on-not to leave work station unattened *Eqiupment-Don't remove without permission *Software dont modify
Procurement:Ensure organisations is getting value fot their money; *Supplier Selection chosen suppliers by: -financial health size, stability; will they last in 18 mths time *Willigness/ability to provide techincal service+maintenance support * Meet delivery requirement-will stick to dates.
Training:All staff use ICT equipment safely in the equipment in the correct manner; *staff-training record kept in human resources- constantly up-to-date*Staff interview with dept head/manager identify stregths/weakness *Staff training plan outlint training *Staff;job description key responsbile+duty+skills required+knowledge to perform job
Topic 6
Legislation:organisations must obey laws that are in place.
CDP 1998;protects authors/owners property of work: *Software*Images*Films*Hardware*Music*Books/manuals. Organisation/firms watch employees because they can damage their image.They will make sure:*Employees not using unathorised/unknown softwre *download music/films,illegally*Policies will be inplace to prevent this;copying images/texts without permission,copying sections from websites without permission,sharing illegally material
CMU 1990;3 stages,committing fraud,hacking computer with intend to alter/delete/see info,Planting virus to crimple an organsiation network. Policies in place to prevent this from happening inorganisations; - Preventation of using/sharing username+passwords=unable to identify personnel - Prevent download=reducing the chance of trojans/virus/worms damaging system
DPA:Protect personal data of data subjects(humans);8principles:1fairly,lawfully processed 2processed for limited purposes 3adepuate relevant+not excessive 4Accurate 5Not kept anylonger than neccesary 6Processed in accordance with d.subject right 7Secure 8not transfered to conutries outside the EU without adequate protection
Topic 6
H&S Act;employers responsible for employee health+must minimise risk of damage to thier health
Polices=protect employees from risks/hazards
inspections on a regular basis on workstations;chairs,keyboards,desks,computer screens
eye tests+glasses;paid for employees when needed
Software:not stressful/frustated to employees
Topic 7
ICT project
Project Seniors= Project sponsor Staff=pjoect sponsor Users of System to be= End user
Project Seniors;before starting,setup two essential aspects for the system;BudgetTime scale
They also the staff given info about feature of the old system(if there's one) & features of the new system
End user;Users that will eventually use the system; will consult with Project Sponsor whenever giving revelant info on the business that the development team can use for the system.
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Ways both parties involvement my help the process
- An agree timescale objectives for reuqirement of the projects
- Timescale & budget argeed on
- Development consult to the end user how the system works; contents of reports produce, interfaces,features
- Meeting on timescale/budget not being exceeded
TEAMWORK: Projects too big for individuals to tackle them alone so instead they complete them by teams.
*Staff realise the importance of working together *budget not exceed * Deadlines are met on projects * Staff; different projects sponsor are expertise in areas=Personnel gain different skills from learning from the other
Topic 7
Factors leading to poor ICT systems
Complexity of the System : system complex for manager to deal with but nottoo complaex they won't know how to use it. e.g MIS - usability simple for all managers to use
Lack of formal methods:system analysts takking shortcuts = system not perfectly system but using methodology - system develop in a formal way. MIS with formal methods developed =
Inadequate inital analysis: Analysis from inexpirenced personnel results in system being useless - not analysis by experinced personnel - information incomplete - take on when testing the system group with doesn't fufil objective because it doesn't function correctly
Lack of management/user involvement:Manager always be involved in project & consult with usesr at each stage of system progression = technically good system.
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Inapporpriate hard/software:Software, easy for managers to take info needed & use choose how to present info. Hardware; no issues with it to effect system causing problems with managers + users of the system.
Lack of management knowledge about ICT systems & ttheir capabilities:ICT specialist; keep up to date info on latests development in there area can't always rely on ICT specialist- only know management should go training course to gain skills and share with group.
Poor Communication:Working together=successful MIS meet demands of users not working together= unsuccessful system + features not in system from user.
Lack of professional standards:British computer society - set minimum standards for pratice to work with. Employer willknow the job by them will be performed in a professional manner. Not all computer professionals are members of the society; so they conform to their own standards
Topic 8
System development life cycle; defines sequences of activities that after computer system is analsyed to designed to implemenated.
System investaged/feasibility: Identifying the problem that the ICT soluion (new system) will solve & writing a project defintion. Start a stragtic due to expense + risk linked with it also it will have aims +objectives.
Feasibnility:Ability to create a system & aims+objectives at a reasonable cost; feasibility report. then it will be determined if the project is a go or not.
Analysing:System analyst analysis the current system or a set of requirement. Which involve the following: *Understanding the existing sysdtem *Gathering+analysising various user requirements *Producing alogical - specification
Design + Specification: Design stage- a complete design + specifications the first step forthe machine to be made; * Designn the system inline of the user requirements *Create the design specification hard/software procedures+personnel
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Build:With plans from the previous stage the system is being built in this stage. Project team personnel expertise in their areas come to produce the system; * Modifying the exisiting software * Producing the working system according to the user requirements *Customing software package to cater to the needs of the organisation
Testing:Once the system is finish = Parts of the system individually tested by members of project team - expertise in their areas. Testing every detailed, higher, system level
Functional:Test userface,validatiy of formulas + it meets system/business requirements. Systems: the whole system is checked used by certain equipment after software is installed.
Operational: Performed by end user on software help to determine if the system will be successful or not. e.g. a website - testing on before or not. e.g. a website - testing on before release
User: Group of user test the software/system
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Installation/Conversion: tge system is full tested & now they project team and now implemenated the following on to the sysem: INSTALL HARDWARE/SOFTWARE *TRAINING OF ALL USERS * CONVERSION OF PREVIOUS DATA
Review & Maintenance: REVIEW; *Client happiness with system *Check requirements + performance is met * Perodic check on system - still meets requirements *help desk facilities = help user who have difficult with system. MAINTENANCE; *Programs - edit added *Programs - New features/function *Meetings - identiifed issues/bugs with machine *Investigate reasons for system crahes
THE NEED FOR SYSTEMATIC FORMAL METHODS=leads to better system
Project mangement;project led by project manager;responsible for the success of the system. *have a plan;show deadlines what will be delivered+when *Have a budget for the project; Project sponsor; at director level; ask for the development of the system; determine if success or not by following; Budget not exceed Complete ontime Requirement shown
Topic 8
Clear time scale; an agreement to time allocated to parts+tasks to projects=determined how long the project will take mile stones; shown when parts of pejects must be completed. IF task time scale draft then project manager will take remedical action to get task back on track.
Agreed deliverables: take up part of system before hand project rteam willknow what they are from clients. Then agreed upon within group when they should be done = show clients for approval
Approval to proceed: the projeect sponosr must sign of the feasibility study from project manager for one project to proceed in the project.
Steps involved in project management: Specification - defines the project which will include; *new system context *system interface-interfacing with other system+ the flow data between them *timescale;deadlines for each part *resources; go back to budget- project manager needs to know how much to spend on certain things e.g. materails.
Breaking down: Complex tasks broke down into smaller tasks; memeber of project know what to do in tasks
Topic 8
Allocating task;Task now given to members of project team who have skills in that particular area.
Estimating time involved to complete the task & hence the project as a whole;This part is majority'guesstimation'. PM allocation for fair amount of time for task to be completed experience PM will get this right because of past experiences
Establishing Controls;PM constant monitor progress of project&budget NOT EXCEED. efficent communications critical between PM &PGs help progress. Reports the meetings take place to update each member on progress rate
Planning for errors;In project PM will have build in extra times for problems e.g. *sickness *staff leaving *technical problems
Development methodologies;two main methodologies linear &iterative
Linear;each task is separte leads to another task- NO LOOP. too rigid to achieve pratice + offers a discipline apporach to system development Task are completed fully 100%
Topic 8
Development methodologies;two main methodologies linear &iterative
Linear;each task is separte leads to another task- NO LOOP. too rigid to achieve pratice + offers a discipline apporach to system development Task are completed fully 100%- problems are dealt with at the time - *Can't go back to make change in the previous stage *This method of work disproves of clients making comments on project in progress * A working version of the project is showed only later on in the development stage
iterative;the project is broken down into stage goes to a cyclic wheel development. End User + developer must be happy with progress in stage before moving on to the next one. In testing/Evaluation if user is unhappy=this is put into account=help make project successful because of learn lessons from previous stages. + User involvement - gives input on solution during development Project learning. As each stage is completed the project improves. More emphisis on user interface/prototyping = more deliverables - User involvement - less time User involvement - greater demands e.g. increase functionality=greater cosdt on budget exceeding it
Topic 8
Choosing: linear; *Large projects - complicated/expensive=less risk+rigorous * Not pressure - the team can perfect each stage *Project clear objects/solution- clearity no need to revisit stages
Iterative; *Project online system - client give constant feedback on development * PTM - experineced - cut out steps which takes the longest * Pressure on the project= user has involvement & give feedback while testing solution.
Other methodologies e.g. Spiral- uses both linear + iterative = team start small and ends up bigger= benefit from learning mistakes from errors/trials
Rapid Prototyping means development time is less
Designing/building done at the same time
Tasks/deliverables are identifed for each step in the spiral methodologies
Topic 9
Investigation techniques
INTERVIEWS; with managers of various departments=problems with legacy system. Input on new system: what functions they would like in the new system to provide them. Operational Staff - do day-to-day work of the organsisation level access - restricted due to their job description. OBSERVATION;watching a worker of a organisation perform his/her job to understand rthe information flows/process they perform on a day-to-day basis.
INSPECTION OF RECORDS: information is still kept on paper based document looking at them, you will understand flow of data/information between department & communcation between org/suppliers/customers Docs with general info:policy/procedure manuals Staff CV Job description Docs with specific info:invoice order forms product catalogues picking lists. QUESTIONNAIRE:draw backs to the method;not always complete, respondents misunderstood questions Good method for collecting large volume of information Complining questionnaire, always have in mind *Avoid leading questions *Structure questionnaires; 1st general questions 2nd specific *Questions well worded - no need to interpret questions
Topic 9
BUSINESS PROCESS MODELLING TOOLS; Decision tables;displays actions when certain conditions occur
Conditionstub;event/situation being tested;cause of the actions in the actions stub that will be taken
Action stub;Taking place due to general action happening in the condition stub
Condition entries indicates which conditions applies Y/N determines if it's applies or not
Action Entries this gives the action depending on the conditions that apply X marked in box shows if action/actions will take be taken
+ all combinations of conditions have been considered Standards layout for all users Easy to follow,information is all in one table Shows cause & effect of events therefore understood by all.
Topic 9
FLOWCHARTS: series of process that should be preferred
Sequence-a list of process carried out one after the other Selection-a neccessary action to take one particular path or another Iteration-a section in the program repeated various of time;3 methods to this
SYSTEM DIAGRAMS: pictorial representation of the functionality of an ICT system. Shows flow of operations in a system + hardware media that are involved in these operations
DATA MODELLING TOOLS; data flow diagrams 'Process/action-represents that does something with the data e.g. manipulate it/calculation 'External sources of data-oval box data comes front goes to 'Data Flow-arrow showing the flow of data in whatever direction 'Storage for data-shows where the data is begins M-Manual Store C-Computer Store Different levels of DFD - level 0context diagram- scope of system
Level 1 Level 2
Topic 9
Entity relationship Models(ERMs) Used for defining info, needs for organsiation to built foundations for an apporaite system to be built. factors named entities properties of factors named attributes now they relate to other called relationships.
ERM-independent of storage/accessing data=not reliant on hardware/software at this stage ERM-representation of data in organisation purpose=produce accurate models of info for the company to use to be able to build an effective system/change the legacy system
describes a system on sets of entities with relationships between them 1-1 1- -
Entity relationship Diagrams(ERD);components in system and their relationships amongst one another. Entity-recorded data e.g. customers, sales,payment Atrritbutes-details abnout entity. Entities relationship; rectangles with arrows linking them together, their attributes can be broke down, if alot they are atomic felxibility to manipluate the daata relationships
entities in the system evaluate to one another 1-1 1-many many-many
2key types; Primary+Foreign; Primary Key:unique key that is different from the other attributes Foreign Key; not Primary Key=not unique
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