a transparent object-oriented schema change approach using

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Page 1: A Transparent Object-Oriented Schema Change Approach Using

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Page 3: A Transparent Object-Oriented Schema Change Approach Using

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Page 5: A Transparent Object-Oriented Schema Change Approach Using

stored data STOREDDATA

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SCHEMA

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stored dataMODIFIEDSTOREDDATA

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remove

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Page 6: A Transparent Object-Oriented Schema Change Approach Using

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Page 7: A Transparent Object-Oriented Schema Change Approach Using

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PersonÏ

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UnderGradÓ

name

gpa

salary

register

defineVC TA’ as Ô( refine Student’:register for TA);

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register for Õ

defineVC Student’ as Ô( refine register for Student);(a)

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(b)Ö

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register

name

gpa

gpa

name

Student×

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advisor

(c)Ö

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salaryadvisor

salaryadvisor

add_attribute

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Page 10: A Transparent Object-Oriented Schema Change Approach Using

Person

name

agename

P1(N1,20)

AgelessPerson

P1(N1)

P2(N2)

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Page 13: A Transparent Object-Oriented Schema Change Approach Using

Car

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Imported

Jeep

color

fuelv

nation

Example Schema

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color

fuelv

nation

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Jeep

color

fuelv

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o1_Jeep&Imported Jeep&Imported

belongs to

o1_conceptual

Intersection−Class Approach

Object−Slicing Approach

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Page 29: A Transparent Object-Oriented Schema Change Approach Using

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Page 35: A Transparent Object-Oriented Schema Change Approach Using

Encore

Orion

Goose

CLOSQL

Rose

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flexibility of Rcomposing schema

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combination of views with schema change

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