Which of the following statements about object oriented databse is not correct?
A. Each object has a unique object identity in the system.
B. Encapsulation and inheritance are two important features of object oriented databasE.
C. A subclass can inherit the attributes and methods of all its superclasses.
D. A subclass includes the attributes and methods of all its subclasses.
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For relation R where primary key contains multiple attributes,no non-key attribute should
A. 1NF
B. 2NF
C. 3NF
D. BCNF
The dung beetles cause an immediate improvement to the quality of a cow pasture.
A. YES
B. NO
C. NOT GIVEN
Dung beetles were brought to Australia by the CSIRO over a fourteen-year period.
A. YES
B. NO
C. NOT GIVEN
TCP service is obtained by having both the sender and the receiver create end points,which
A. network address
B. supernet address
C. socket
D. IP address