1. CS 3630 Database Design and Implementation
21 slides
MUST go over A2 for Quiz1 next class

2. Structural Constraints
Participation
Total (Mandatory)
Partial (Optional)
Cardinality
Max number of occurrences that can be related to one occurrence
Staff      Oversees PropertyForRent
Business Rules

3. Structural Constraints: Multiplicity
Combination of Participation and Cardinality
Multiplicity of Binary Relationship
one-to-one
one-to-many
many-to-many

4. Multiplicity: one-to-one
Staff (1..1) Manages (0..1) Branch
Each branch has exactly one manager.
Each staff manages zero or one branch.
Staff
staffNo
Manages
Branch
branchNo
1..1
0..1
For one object on the other side!

5. Multiplicity: one-to-many
Staff (0..1) Oversees (0..*) PropertyForRent
Staff
staffNo
Oversees
PropertyForRent
propertyNo
0..1
0..*
One property is overseen
by 0 or 1 staff
One staff oversees
0 or more properties
For one object on the other side!

6. Specifying Multiplicity Range
Staff (0..1) Oversees (0..30) PropertyForRent
Staff
staffNo
Oversees
PropertyForRent
propertyNo
0..1
0..30
One property is overseen
by 0 or 1 staff
One staff oversees
At most 30 properties

7. Multiplicity: many-to-many
NewsPaper (0..*) Advertises (1..*) PropertyForRent
Advertises
NewsPaper
newspaperName
PropertyForRent
propertyNo
0..*
1..*
One newspaper has Ads for 1 or more properties
One property is advertised on zero or more newspapers
For one object on the other side!

8. Structural Constraints: Multiplicity
Multiplicity of Complex Relationship (n-ary)
When (n-1) values are fixed for other entities

9. Multiplicity for Complex Relationship
Client (0..*) Registers with Staff (0..1) at Branch (0..1)
Registers
Branch
Staff
0..1
0..1
0..*
Client

10. Multiplicity: Summary
Symbols Meaning
Zero or one
Exactly one
Exactly one
0..* Zero or more
1..* One or More
Between 5 and 10, inclusive
0, 3, Zero, three, six, seven, or eight
Total: low limit > 0
Partial: low limit = 0

11. Sample E-R Model

12. Open everything, but do it yourself!
Quiz1
Wednesday, Feb 14, Lab 206
Using Computers
Open everything, but do it yourself!
Download Word Document from D2L
Type your answers.
Upload Completed Document to D2L

13. Assignment3