SYSTEMS ANALYSIS & DESIGN PHASE 3 SYSTEMS DESIGN Input Design

Chapter 7 Input Design

Objectives Discuss the objectives of systems input design Explain the differences among data capture, data entry, and data input Explain the differences between batch and online input List and describe the different types of data validation checks Discuss effective source document design

Objectives Design input records Discuss guidelines for effective screen design Describe and design data entry screens, process control screens, graphical user interfaces, and Help screens Explain input control techniques

Introduction Input technology has changed greatly Output quality depends on input quality Main objectives of input design User-friendly interface Input processes that ensure data quality, accuracy and timeliness Click to see Figure 7-1

Input Design Objectives Definitions Data capture Identification and recording of source data Data entry Conversion of source data into a computer-readable form Data input Process by which the computer-readable source data enters the information system

Input Design Objectives Four main input design objectives 1. Select input media and methods 2. Develop efficient input procedures 3. Reduce input volume 4. Reduce input errors

Input Design Objectives Input media and data entry methods Batch input method Data entry is done over period of time Collection (batch) of data is input at one time Online data entry method Also called direct data entry Data is validated and available immediately Click to see Figure 7-2

Input Design Objectives Input media and data input methods Source data automation Combines online data entry with online data capture Uses magnetic data strips and swipe scanners Common examples: ATMS, point-of-sale terminals, bar code readers, patient ID bracelets, libraries

Input Design Objectives Develop efficient input procedures Procedures Must be efficient, timely, and logical Must identify potential bottlenecks

Input Design Objectives Reduce input volume Less volume means less time, effort, and cost Four guidelines 1. Input necessary data only 2. Do not input data that can be retrieved from system files or calculated from other data 3. Do not input constant data 4. Use codes Click to see Figure 7-3

TRADEOFF Should users ever enter retrievable data for verification purposes? Online data entry allows immediate verification, but batch input methods do not Batch input data can be verified by entering a second data item, such as a customer name in addition to a customer number, which must match a specific record when the data is input Pros and cons: this method can detect invalid entries, but involves more time and expense

A KEY QUESTION Should Prowler Products change to an online data entry system? Pros: improved data accuracy, customer satisfaction, and company image Cons: more expensive Are these valid reasons to change? What cost-benefit issues should be analyzed? What factors should be considered?

Input Design Objectives Reduce input errors Fewer errors mean better data quality Eight types of data validation checks 1. Sequence checks 2. Existence checks 3. Data type checks 4. Range checks 5. Reasonableness checks 6. Validity checks 7. Combination checks 8. Batch controls

Key Tasks in Input Design Six key tasks 1. Design data entry and input procedures 2. Design source documents for data capture, or devise other data capture methods 3. Design input data records 4. Design data entry screens 5. Design user interface screens 6. Design audit trails and system security measures

Source Document Design Source documents Request and collect input data Can trigger or authorize input actions Provide a record of the original transaction Form layout guidelines Allow sufficient space Offer clear instructions Provide logical organization Use captions effectively Click to see Figure 7-4

Source Document Design Form zones Heading zone Control zone Instruction zone Totals zone Authorization zone Source documents can be external or internal Click to see Figure 7-5 Click to see Figure 7-7 Click to see Figure 7-6 Click to see Figure 7-8 Click to see Figure 7-9

Input Record Design Input record layout chart To design and document batch input records Multiple record designs are used for transactions that involve constant and repeating data Constant fields (non-repeating data) Repeating fields Click to see Figure 7-10 Click to see Figure 7-11

Input Record Design Information flow on a form Should be logical and easy to follow Click to see Figure 7-12

Input Record Design Information flow on a form Should be logical and easy to follow Poor design results in forms that are difficult to use, time-consuming, and prone to error Click to see Figure 7-13

Screen Design Effective screen design guidelines 1. Screens should be attractive and uncluttered 2. Information on a single screen should be displayed in a meaningful, logical order 3. Screen designs should be consistent 4. Messages should be specific, understandable, and professional 5. Messages should remain on the screen for an appropriate period of time Click to see Figure 7-14

Screen Design Effective screen design guidelines 6. Special effects should be used sparingly 7. Users should receive feedback 8. Screen designs should be documented and approved as soon as possible Click to see Figure 7-14

Screen Design Data entry screen design Guidelines 1. Restrict user access to screen locations where data is entered 2. Provide a descriptive caption for each field and show the user where to enter the data 3. Show a sample format if one is required 4. Require ending keystroke for every field 5. Do not require users to enter special characters Click to see Figure 7-15 Click to see Figure 7-16

Screen Design Guidelines 6. Do not require users to type leading zeroes or trailing spaces for alphanumeric fields 7. Do not require users to type trailing zeroes that follow a decimal point 8. Display default values that users can accept 9. Use default values for constant data 10. Display a list of acceptable values for fields with a limited number of valid choices

Screen Design Guidelines 11. Provide a way to leave the data entry screen without inputting the current record 12. Provide an opportunity to confirm the accuracy of input data before entering it 13. Provide a means to move among form fields in a standard, or in another, order 14. Design the screen form to match the layout of the source document Click to see Figure 7-17

Screen Design Guidelines 15. Allow the operator to add, change, delete, and view records 16. Design a method to allow operators to search for a specific record

TRADEOFF When should input data be validated? Is it better to check the values as soon as each value is entered, or wait until all fields are input? What issues should be considered? What type of field is involved, and does it affect other fields? Can data be validated at time of entry? Can missing data be obtained later? Which method do users prefer?

A KEY QUESTION At Boolean Toys, should individual users be allowed to select data entry and validation methods, or should a standard method be required? What are the pros and cons of allowing different validation methods in the same system?

Screen Design Process control screen design Users can control system actions with interactive menus and prompts Menu screens Menus display a list of user-selectable options Click to see Figure 7-18

Screen Design Process control screen design Users can control system actions with interactive menus and prompts Menu screens Menus display a list of user-selectable options Menu-driven system uses a hierarchy of main menus and submenus Shortcut key combinations can be used in a menu design Click to see Figure 7-19

Screen Design Process control screen design Prompt screens User types a response to a prompt Click to see Figure 7-20

Screen Design Process control screen design Prompt screens User types a response to a prompt Responses can include commands Click to see Figure 7-21

Screen Design Process control screen design Prompt screens User types a response to a prompt Responses can include commands Structured Query Language (SQL) can be used Question/answer screens can be used Natural language techniques can be used, similar to Internet search engines Click to see Figure 7-22

Screen Design Process control screen design Combination screens Menus and prompt screens can be combined effectively Click to see Figure 7-23a Click to see Figure 7-23b

Screen Design Graphical user interfaces A GUI environment includes process control and data control A GUI environment is easy to use Common features Menu bar Toolbar Click to see Figure 7-24

Screen Design Common features Menu bar Toolbar Drop-down menus Click to see Figure 7-25

Screen Design Common features Menu bar Toolbar Drop-down menus Dialog, text, and drop-down list boxes Click to see Figure 7-26

Screen Design Common features Menu bar Toolbar Drop-down menus Dialog, text, and drop-down list boxes Option (radio) buttons Click to see Figure 7-27

Screen Design Common features Menu bar Toolbar Drop-down menus Dialog, text, and drop-down list boxes Option (radio) buttons Spin bars Click to see Figure 7-28

Screen Design Help screen design Several methods to obtain Help Click a command button or toolbar Press a special key Context-sensitive Help Provides Help on the task in progress Click to see Figure 7-29

Screen Design Help screen design Several methods to obtain Help Click a command button or toolbar Press a special key Context-sensitive Help Provides Help on the task in progress User-selected Help Hypertext Uses links to display additional information on related topics Click to see Figure 7-30

Screen Design Design guidelines Provide a direct route for users to return to the program after Help is obtained Title every Help screen Use easy, simple, understandable Help text Present attractive, uncluttered screens Provide appropriate examples Use hyperlinks Include contact data for persons or departments responsible for assisting users

Input Control Measures to ensure that data is correct, complete, and secure Effective source document design Data validity checks Batch input controls Log files for rejected records Audit trails Data security measures, including encryption Password and sign-on procedures Records retention policies Click to see Figure 7-31

Automated Design Tools Screen and form generators Useful tools during input design as well as output design Screen and form generators interact with the data dictionary Screens and forms can include built-in field validation checks Mock-ups can be produced quickly for user approval, together with design specifications

SOFTWEAR, LIMITED SWL will use the Pacific Software Solutions payroll package, and develop its own ESIP system Rick Williams and Becky Evans will attend Pacific’s train-the-trainer workshop Tom Adams, programmer/analyst, will work on the inputs, forms, and switchboards for the ESIP system

SOFTWEAR, LIMITED ESIP Option Form tasks Design the source document Click to see Figure 7-32

SOFTWEAR, LIMITED ESIP Option Form tasks Design the source document Design a matching data entry screen Click to see Figure 7-33

SOFTWEAR, LIMITED ESIP Option Form tasks Design the source document Design a matching data entry screen Create mockups Obtain approval Click to see Figure 7-34a Click to see Figure 7-34b

SOFTWEAR, LIMITED ESIP Deduction Authorization Form tasks Design the source document Design a matching data entry screen Create mockups Obtain approval Click to see Figure 7-35

SOFTWEAR, LIMITED ESIP Deduction Authorization Form tasks Design the source document Design a matching data entry screen Create mockups Obtain approval Click to see Figure 7-36 Click to see Figure 7-37 Click to see Figure 7-38

SOFTWEAR, LIMITED Switchboard design Uses command buttons, icons, and push buttons to allow users to select data entry screens and other options Provides users with Help Provides a way to exit from the ESIP system Click to see Figure 7-39

SOFTWEAR, LIMITED Tom started by designing the ESIP Option Form, which would be a source document Next, Tom designed a matching data entry screen Finally, Tom created mockups and obtained approval Click to see Figure 7-39