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subclasses STUDENT and STAFF copy the attributes of superclass PERSON. The
translated OODB schema can be shown below:
&ODVV3(56212,'66LQWHJHU1DPHVWULQJ
&ODVV&2856(2,'&RXUVHQRLQWHJHU&RXUVHQDPHVWULQJ3
VWXGHQW
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67$))
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,16(573(5621661DPHYDOXHµ-RKQ'RH¶
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By following the algorithm insert, we can translate the SQL statement to the fol-
lowing OSQL statement by locating the composite objects that contain the to-be-
inserted object, and insert the to-be-inserted object with the aggregate attributes
pointing to the composite objects as:
,16(57LQWR3(5621661DPHYDOXHµ-RKQ'RH¶
6(/(&7IURP'(3$570(17ZKHUH'HSWQDPH µ&6¶LQWR2,'
FV
,16(57LQWR67$))6WDII3RVLWLRQ3
GHSDUWPHQW
YDOXH3URIHVVRU
2,'
FV
However, if John Doe resigns, we need to remove his record from the CS depart-
ment. The SQL for the delete statement is:
'(/(7(IURP67$))ZKHUH6WDII
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