Conceptual and Physical Models

• A design for an object (a car, a house, a database, etc.) which includes implementation details such as size, volume, weight, etc. - Physical model
•  A data model, usually represented by an entity-relationship diagram. conceptual model
•  A collection of facts from which conclusions may be drawn. Data
• The process of capturing the important concepts and rules that shape a business and depicting them visually on a conceptual model- data modelling

1.            You will be working in pairs for this activity.

•             One student describes his/her “dream house” while the other student attempts to draw it.

You can discuss specific details, but the student describing the house is not allowed to see what is being drawn until after time is called.

•             After sharing your drawing, describe the importance of accurately describing information requirements.

To accurately design physical model, capture all business rules and take in account rules governing the future system.

2.            Review the scenario below. Identify the conceptual model and the physical model from the scenario.

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Conceptual:

Zoe was about to go into a store to purchase drinks for the birthday party scheduled for that evening. Zoe knows that she needs drinks for 48 people and is expecting the store to accept a check for payment and to provide her with some assistance carrying the product to her car. Zoe wants to have carbonated drinks, non-carbonated drinks, and sugar free drinks. She is expecting to purchase eight six-packs.

Physical:

 Zoe enters the store and discovers the entire drink distribution system is automated. She also discovers that the drinks come in varying package sizes and that she must choose the correct vend-ing option for the products to be disbursed. Drinks are packaged in four-packs, six-packs, and ten-packs.

3.            Provide five reasons for creating a conceptual data model.

1.            Describes exactly the information needs of the business

2.            Facilitates discussion

3.            Prevents mistakes and misunderstandings

4.            Forms important “ideal system” documentation

5.            Forms a sound basis for physical database design.

4. List two examples of conceptual models and physical models.

Conceptual Model:

Physical model: