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From Michael Watzek <mwa.t...@spree.de>
Subject Schema files implementing inheritance proposal
Date Thu, 28 Jul 2005 12:54:16 GMT
Hi,

Craig suggested to begin the discussion about the inheritance proposal 
with schema files. Attached you find schema files for application 
identity for each inheritance mapping:

- schema.sql implements mapping 1:
This is the schema file in your TCK20 workspace. Thus, I did not attach it.

- schema1.sql implements mapping 2:
Separate table for each class in the inheritance hierarchy. Each table 
contains columns for the declared fields. See tables "persons", 
"employees", "parttimeemployees", "fulltimeemployees", "insuranceplans", 
"medicalinsurance", and "dentalinsurance".

- schema2.sql implements mapping 3:
Separate table for each class in the inheritance hierarchy. No tables 
for abstract classes. Each table contains columns for all fields. 
Managers, mentors, hradvisors, and employees of the month are fulltime 
employees. Only fulltime employees can have insurances, can be project 
members, and can be project reviewers. Separate phone number type tables 
for persons, fulltime employees, and parttime employees. See tables 
"persons", "parttimeemployees",  "fulltimeemployees", 
"medicalinsurance", "dentalinsurance", "fulltime_employee_phoneno_type", 
and "parttime_employee_phoneno_type".

- schema3.sql implements mapping 4:
Person has inheritance strategy "new-table. Employee has inheritance 
strategy "subclass-table". PartTimeEmployee and FullTimeEmployee have 
inheritance strategy "new-table". Insurance has inheritance strategy 
"subclass-table". MedicalInsurance and DentalInsurance have inheritance 
strategy "new-table". See tables "persons", "parttimeemployees", 
"fulltimeemployees", "medicalinsurance" and "dentalinsurance".

- schema4.sql implements mapping 5:
Person, Employee, and Insurance have inheritance strategy "new-table". 
PartTimeEmployee, FullTimeEmployee, MedicalInsurance, and 
DentalInsurance have inheritance strategy "super-class". See tables 
"persons", "employees", and "insuranceplans".

Please comment!

Regards,
Michael
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Michael Watzek                  Tech@Spree Engineering GmbH
mailto:mwa.tech@spree.de        Buelowstr. 66
Tel.:  ++49/30/235 520 36       10783 Berlin - Germany
Fax.:  ++49/30/217 520 12       http://www.spree.de/
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