Figure 3: Supertype/subtype relationship and associated table mappings
Table Name Column Name Data Type Length Key Status Required Indexed Column Description
PERSON PersonID Integer 4 Pkey Yes Yes Unique identifier for each person
FirstName Text 20 Yes Yes Person's first or given name
Minit Text 1 Initial of person's middle name
LastName Text 30 Yes Yes Person's last or surname, family name
Address Text 60 Full residence address, including street number & name, city, state code, & zip code
Phone Text 30 Maybe Contact phone number for this person, include area code
Email Text 60 Maybe Contact email address for this person
EMPLOYEE PersonID Integer 4 Pkey, Fkey Yes Yes Unique identifier for each person, link back to table PERSON
EmpSSN Text 12 Eventually Yes SSN for employee, required by tax law
HireDate Date Date (mm/dd/yyyy) that employee was hired and began work
AUTHOR PersonID Integer 4 Pkey, Fkey Yes Yes Unique identifier for each author, links back to table PERSON
PayToOrderOf Text 50 Who to make the paycheck out to
PayToTaxID Text 15 SSN or TaxID number for the paycheck
PayToAddress Text 60 Mailing address for the paycheck