Database Reference
In-Depth Information
EMPLOYEE
Salary
DeptCode
EmployeeJob
EmpFirstName
Multivalued
Single-Valued
ModelYear
ExteriorColor
ModelDesc
Make
AUTOMOBILE
Figure 7-8
Single-valued and multivalued attributes.
SuiteNo
StreetName
DoorNo
City
Street
Composite
State
CustomerAddress
CustomerName
Zip
CUSTOMER
CustomerPhone
CreditCode
Figure 7-9
Composite attribute.
Entity type:
EMPLOYEE
Composite attribute:
EmployeeName
Component simple attributes:
FirstName, LastName, MidInitial
Simple
Entity type:
LOAN ACCOUNT
Simple attribute:
LoanAmount
Entity type:
EMPLOYEE
Simple attribute:
SocialSecNumber
Figure 7-9 shows the notations used for representing composite attributes. Note
how the composite attribute branches into the simple attributes that are its com-
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