1. Tutorial 3
Data Modelling

2. Why do data modelling?
Conceptual Logical view of data structures & attributes required in inter-process flows
Documented Observations/Meetings/Interviews
Other Work Documents of all sorts eg Policies, Procedural Guides
Read, comprehend & translate
Business Process Modelling
Logical Data Modelling using UML Notations
Data Modelling
Eg using BPMN notations
Physical Data Modelling using MS Access Entity Relationship Diagram Notations
Selected Database System Implementation view of data structures & attributes required in inter-process flows

3. Data Modelling Paradigms
Database organisation concepts:
ICT Terms Excel or Access Terms
Data files Data tables
Data fields/attributes Data table columns
Records (groups of fields) Data table rows
Database Groups of Data Files stored in a server machine
Data File / Table
Database – Interlinking Data Files/Tables
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)

4. Logical Data Modelling using UML Notations
Data File / Table
Database – Interlinking Data Files/Tables
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
Column 1
(Field 1)
….. ……
Column N
(Field N)
Row 1
(Record 1)
Data
……..
Row N
(Record N)
We visually describe their relationships using data modelling languages
Some fields are primary or foreign keys of data files/tables
Logical Data Modelling using UML Notations
Physical Data Modelling using MS Access Entity Relationship Diagram Notations
Metaphor example: Cantonese dialect
Eg Mandarin dialect

5. Physical Data Modelling MS Access Entity Relationship Diagram Modelling
The work you did for Part 2 sets up the data tables (ie data entities), and the keys and relationships and model them in the MS Access Relationship Screen

6. Review Tutorial Tasks

7. Tutorial Activity 3
Bunnings has operations in every Australian State. Each department can employ multiple employees (or no employee), but each employee must be assigned to one department only. Every sales order made must be assigned to one employee, and each employee can generate multiple sales orders (but it is possible that an employee will have no sales at all). Each sales order must include at least one product, and each product type can be sold many times.
Which org perspective are you modelling? A Bunning’s state operation’s data model
Identify NOUNS and linking VERBS List of NOUNS  Data Files List of VERBS  Data Files’ Relationship-lines/links
Data entities are interlinked by relationship lines, described in terms of an explanation label and multiplicities
From the 2 lists, draw the data entity boxes and link them by using the:
verbs to label/describe their relationship-lines and
descriptive quantities to label the multiplicities
Relationship List:
Employs or Assigns – links department & employee
Generates – links employee & sales orders
Includes – links sale orders and products
{Classifies} – links product & product type
Data Entities List:
Department
Employee
Sales Order
Product
Product Type

8. Bunnings has operations in every Australian State
Bunnings has operations in every Australian State. Each department can employ multiple employees (or no employee), but each employee must be assigned to one department only. Every sales order made must be assigned to one employee, and each employee can generate multiple sales orders (but it is possible that an employee will have no sales at all). Each sales order must include at least one product, and each product type can be sold many times.
 classifies
1..*
1..1
Product
Product Type
1..* 
Includes
1..1
 generates
0..*
1..1
Sales Order
Employee
Relationship List:
Employs or Assigns – links department & employee
Generates – links employee & sales orders
Includes – links sale orders and products
{Classifies} – links product & product type
0..* 
Employs/assigns
Data Entities List:
Department
Employee
Sales Order
Product
Product Type
1..1
Department

9. Tips One PRODUCT TYPE classifies one to many PRODUCT/S
One PRODUCT is classified by one PRODUCT TYPE
 classifies
1..*
1..1
Product
Product Type
1..*
One SALES ORDER includes one to many PRODUCT/S
One PRODUCT is included in one SALE ORDER 
Includes
1..1
 generates
0..*
1..1
Sales Order
Employee
0..*
One EMPLOYEE generates zero to many SALE ORDER/S
One SALES ORDER is generated by one EMPLOYEE 
Employs/assigns
1..1
Department
One DEPARTMENT employs zero to many EMPLOYEE/S
One EMPLOYEE is employed by one DEPARTMENT Or
One DEPARTMENT assigns zero to many EMPLOYEE/S
One EMPLOYEE is assigned by one
Tips
Active Voice
Vs Passive Voice descriptions for relationships
Always start with One

10. Given Answer  classifies 1..* 1..1 Product Product Type 1..* 
Example for the GIVEN ANSWER
Product Types Products
Apple Fiji, Gala, Granny Smiths, etc
Orange Navel, Valencia, etc
Berry Strawberry, blueberry, etc
A sales order includes various apples & oranges only (no berries).
Hence PRODUCT TYPE of “Berry” is NOT included in the sales order - that is why One PRODUCT (TYPE) may NOT be included in a SALES ORDER
1..*
1..1
Product
Product Type
1..* 
Includes
1..1
 generates
0..*
1..1
Sales Order
Employee
Same meanings
0..*
Given Answer 
Employs/assigns
1..1
(Type)
Department

11. Tutorial Activity 4
Dr Franklin runs a small medical clinic specializing in family practice
She has many patients. Patients are established in the database prior to the first patient visit.
When the patients visit the clinic, she may perform several tests to diagnose their conditions. She bills the patient one amount for the visit plus additional amounts for each test. Assume a patient visit could take place without any diagnostic tests and that the tests are established in the database before they are used by Dr Franklin.
Which org perspective you are data modelling? Dr Franklin’s Medical Clinic’s data requirements
List of key Nouns identified:
Patient
Patient Visit (medical consultation, which is like ERP sales transaction)
Diagnostic Test
List of Relationship descriptors
Visits (attends or comes to) - links patients and consultation
Takes place (involves or includes) – links consultations & tests

12. Tutorial Activity 4
Dr Franklin runs a small medical clinic specializing in family practice
She has many patients. Patients are established in the database prior to the first patient visit.
When the patients visit the clinic, she may perform several tests to diagnose their conditions. She bills the patient one amount for the visit plus additional amounts for each test. Assume a patient visit could take place without any diagnostic tests and that the tests are established in the database before they are used by Dr Franklin.
Patient
1..1
Attends / comes to 
0..*
Medical
Consultation
(Patient Visit)
0..*
List of key Nouns identified:
Patient
Patient Visit (medical consultation, which is like ERP sales transaction)
Diagnostic Test
List of Relationship descriptors
Visits (attends or comes to) - links patients and consultation
Takes place (involves or includes) – links consultations & tests
Involves/Includes 
0..*
Diagnostic Test

13. Tutorial Activity 4
Dr Franklin runs a small medical clinic specializing in family practice
She has many patients. Patients are established in the database prior to the first patient visit.
When the patients visit the clinic, she may perform several tests to diagnose their conditions. She bills the patient one amount for the visit plus additional amounts for each test. Assume a patient visit could take place without any diagnostic tests and that the tests are established in the database before they are used by Dr Franklin.
Patient
1..1
Attends / comes to 
0..*
Medical
Consultation
(Patient Visit)
0..*
Involves/Includes 
One PATIENT attends zero to many CONSULTATION/S
One CONSULTATION is attended by one PATIENT
One CONSULTATION involves zero to many TEST/S
One TEST is involved in zero to many CONSULTATION/S
0..*
Diagnostic Test

14. Tutorial Activity 4 Given Answer Patient 1..1 Attends / comes to 
0..*
Medical
Consultation
(Patient Visit)
0..*
Involves/Includes 
0..*
Diagnostic Test
Given Answer

15. Tutorial Activity 5: More ERP events explicit
Which organisation perspective are you data modelling? Joe’s Ice Cream Sales Ordering & Fulfilment processes
List of Nouns:
Customers
Sales Transaction
Sales/Cash Receipts
Products
{Product Type} – Ice-cream cones, sundaes or shakes
{Employee} – one selling the products and another depositing sales receipts (the cash monies)
List of Relationships (note many are implicit (ie you have to define yourself using ERP knowledge)
{Serves} - links employees & sales transactions
{Buys} – links customers & sales transactions
Pays – links customers & cash receipts
{Receives} – links employees and sales/cash receipts
{Leads to/results} – links sales and sale/cash receipts
Deposits – links sales/cash receipts & Cash (Bank Account)
Includes – links Sales transactions & products
{Classified} – links products and implied product types
Joe’s is a small ice-cream shop located near the local university’s football ground. Joe’s serves walk-in customers only. The shop carries 26 flavours of ice cream.
Customers can buy cones, sundaes or shakes. When a customer pays for an individual purchase, a sales transaction usually includes just one item. When a customer pays for a family or group purchase, however, a single sales transaction includes many different items.
All sales must be paid for at the time the ice cream is served.
Joe’s maintains several banking accounts but deposits all sales receipts into its main checking account

16. Tutorial Activity 5: More ERP events explicit
Joe’s is a small ice-cream shop located near the local university’s football ground. Joe’s serves walk-in customers only. The shop carries 26 flavours of ice cream.
Customers can buy cones, sundaes or shakes. When a customer pays for an individual purchase, a sales transaction usually includes just one item. When a customer pays for a family or group purchase, however, a single sales transaction includes many different items.
All sales must be paid for at the time the ice cream is served.
Joe’s maintains several banking accounts but deposits all sales receipts into its main checking account
Product Type
1..1
Classifies ↓
1..*
 serves
 includes
Product
Sales (Order) Transaction
(Sales)
Employee
1..1
0..*
1..*
0..*
1..1
 transacts/buys
Customer
Results in /leads to ↓
1..1
 pays
One PRODUCT TYPE (eg cones, sundaes, milkshakes) classifies one to many PRODUCTS (eg vanilla, strawberry ice-cream cones, etc)
One PRODUCT is classified by one PRODUCT TYPE
One SALES includes one to many PRODUCT/S
One PRODUCT is included zero (unsold ice-cream products) to many SALE/S
One SALES leads to/results in only one CASH RECEIPT
One CASH RECEIPT is a result of only one SALES
One CASH BANK ACCOUNT receives deposits of zero to many CASH RECEIPTS
One CASH RECEIPT can only be deposited in only one CASH Bank Account
One (Sales) EMPLOYEE serves zero to many SALES
One SALES is served by one (sales) EMPLOYEE
One CUSTOMER transacts zero to many SALES
One SALES is transacted by one CUSTOMER (at a time)
One CUSTOMER pays zero to many CASH RECEIPT/S
One CASH RECEIPT is paid by one CUSTOMER (at a time)
One (Payment Admin) EMPLOYEE receives zero to many CASH RECEIPT/S
One CASH RECEIPT is received by one EMPLOYEE (at a time)
1..1
Cash (Bank Account)
1..1
0..*
Cash Receipts
(Monies)
(Payment Admin)
Employee
0..*
1..1
 deposits
 receives
(See relationship descriptions in NOTES sections of this slide)

17. REA – Resource, Events & Agents Formatted Data Models
See Text books for these definitions
REA is a diagram formatting technique for guiding new data modellers to organise and format their data models by grouping:
Resource entities on your Left Hand Side
Event entities in the middle
Agent entities on your Right Hand Side
Of your drawing page
Experienced data models don’t necessarily use this formatting guideline, especially when modelling more complex data models
REA formatted Data Model EXAMPLE
RESOURCES
EVENTS
AGENTS