Explain The Distinction Between A Type X And A Reference Type Ref(x).

1.	Explain The Distinction Between A Type X And A Reference Type Ref(x). Under What Circumstances Would You Choose To Use A Reference Type?
Answer» If the type of an ATTRIBUTE is X, then in each tuple of the table, corresponding to that attribute, there is an ACTUAL object of type x . If its type is ref(x), then in each tuple, corresponding to that attribute, there is a reference to some object of type x. We choose a reference type for an attribute, if that attribute’s intended PURPOSE is to refer to an independent object. If the type of an attribute is x, then in each tuple of the table, corresponding to that attribute, there is an actual object of type x . If its type is ref(x), then in each tuple, corresponding to that attribute, there is a reference to some object of type x. We choose a reference type for an attribute, if that attribute’s intended purpose is to refer to an independent object.

Explain The Distinction Between A Type X And A Reference Type Ref(x). Under What Circumstances Would You Choose To Use A Reference Type?

Answer»

If the type of an ATTRIBUTE is X, then in each tuple of the table, corresponding to that attribute, there is an ACTUAL object of type x . If its type is ref(x), then in each tuple, corresponding to that attribute, there is a reference to some object of type x. We choose a reference type for an attribute, if that attribute’s intended PURPOSE is to refer to an independent object.

If the type of an attribute is x, then in each tuple of the table, corresponding to that attribute, there is an actual object of type x . If its type is ref(x), then in each tuple, corresponding to that attribute, there is a reference to some object of type x. We choose a reference type for an attribute, if that attribute’s intended purpose is to refer to an independent object.

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