There are some correlations between relational data base terminology and object-oriented database
terminology. Which of the following relational model terms, respectively, correspond to the object
model terms of class, attribute and instance object?
A.
Relation, column, and tuple
B.
Relation, domain, and column
C.
Domain, relation, and column
D.
Relation, tuple, and column
Explanation:
Table shows the correspondence between the two models. In comparing the two models, a class is
similar to a relation; however, a relation does not have the inheritance property of a class. An
attribute in the object model is similar to the column of a relational table. The column has limitations
on the data types it can hold while an attribute in the object model can use all data types that are
supported by the Java and C++ languages. An instance object in the object model corresponds to a
tuple in the relational model. Again the data structures of the tuple are limited while those of the
instance object can use data structures of Java and C++.