systems analysis

systems analysis

1. what is system analysis ?

   • the systems that we are talking about are the systems within organizations and businesses, systems of communication, financial systems, manufacturing systems , etc. Basically the systems that make the organization or business work.

2. research

   • before the system analyst can make any recommendations about a new system, they first have to understand how the present system works
     • questionnaires
       • with large groups of people a questionnaire is a quick and simple way to gather information.
     • collecting information
       • as much information about the present system needs to be gathered as possible
     • interviews
       • the system analyst can interview key people within the system to find out how it works
     • collecting documents
       • most businesses and organizations use documents to record information, or to communicate information .

3. Designing

   • System Inputs
     • Process
       • Data must be captured
         • It can be manual or automatic
       • Data must be input to the computer
     • Types of methods to do the data cature and data input
       • Paper Forms
         • They have spaces for numbers and text to be written in. The data from this form would then be typed into the computer manually or by a OMR
       • Bar Code Reader
         • Captures the numeric code that the barcode represents. They are used with POS systems and also stock-control systems
       • Card Reader
         • Cards contain data stored on a magnetic strip or in smart cards which can be captured with a card reader, they are mostly used in systems such as EFTPOS
       • Camara
         • It captures still or moving images which can then be input to a computer for processing
   • On-screen Forms
     • It should have:
       • *Have all of the necessary fields *Have obvious places for user inputs *Use appropriate controls for each field *Have text box controls that are the right size for the data *Have easy-to-understand instructions *Make good use of the screen area available
     • Form Controls
       • Text Box
         • Normal text input
       • Buttons
         • Perform an action
       • Option Buttons
         • To select options
       • Check Boxes
         • Select options
       • Drop-Down menus
         • Select options from a list
     • Validation and Verifications techniques
       • Validation
         • The computer checks that the data is sensible
           • Presence Check
           • Range Check
             • Is the data value within a set range?
           • Length Check
             • Is an item of text too short or too long?
           • Type Check
           • Format Check
       • Verification
         • To check that data is the correct value
           • Proof Reading
             • After the data has been entered a person compares the original data with the data in the computer
               • Advantages and Disadvantages
                 • Proof-reading is quick and simple, but doesn’t catch every mistake.
           • Double-Entry
             • The data is entered into the computer twice
               • Advantages and Disadvantages
                 • Double-entry takes more time and effort, but it catches almost every mistake.
   • System processes
     • Data and File structures
       • A data structure is an organised collection of data, this will be some sort of database in which data will be stored as it is being processed
       • Needs to concider
         • *The type of data being stored *The size of the data *The field names to use How many records will need to be stored
       • Backing storage device and media
         • *How often will the data need to be accessed *How quickly the data needs to be accessed *How large will the data files be So, for example
     • How the Data Will be Processed
       • The system designer also needs to design the actual steps to be followed to processing the data
   • System Outputs
     • On-Screen Reports
       • The designer should consider
         • *Show all of the necessary fields *Have fields that are the right size for the data *Have easy-to-understand instructions *Make good use of the screen area available *Make good use of colours and fonts to make the data clear
     • Printed Reports
       • The report needs to fit a piece of printer paper, it might also include page numbers, a header / footer, etc