Homework

1
Homework 3 Results

• Total points 166
• Overall grades
• Average 132.8 or 80
• Minimum 0
• Maximum 163
• Standard Deviation 51
• Excluding zeros
• Average 151.7 or 94.8
• Minimum 120
• Maximum 163
• Standard Deviation 8.65

2
Relational Database Development So Far

• E-R diagrams
• Entities essential data elements
• Attributes data element descriptors
• Entity linkage categories relationships,
  connectivity, cardinality
• Relational Database Models
• Tables correspond to entities
• Fields correspond to attributes
• Relationships correspond to business rules,
  connectivity
• Basic queries
• Relational Database Applications
• Data management
• Tables
• Forms

How do we bring it all together in a real-world
setting?
3
Health Inspection Problem Extensions - I

• Inspection event may be represented two ways
• transaction-in-rows
• transaction-in-columns
• Example

vs
What are the pros and cons of each approach?
4
Health Inspection Problem Extensions- II

• Permit could be treated as
• attribute of ESTABLISHMENT
• separate entity
• Example

vs
What are the pros and cons of each approach?
5
Health Inspection Problem Extensions- III

• INSPECTION and PERMIT (if included as an entity)
  could be treated as
• one-to-one related with ESTABLISHMENT (snapshot)
• many-to-one related with ESTABLISHMENT (life
  cycle)

What are the pros and cons of each approach?
6
School Bus Garage E-R Diagram
7
School Bus Garage Case Relational Database Schema