When The Optional Properties Are Learned?

1.	When The Optional Properties Are Learned?
Answer» An optional property is used only if the OBLIGATORY properties do not provide UNIQUE IDENTIFICATION of an OBJECT. An optional property is used only if the obligatory properties do not provide unique identification of an object.

Answer»

An optional property is used only if the OBLIGATORY properties do not provide UNIQUE IDENTIFICATION of an OBJECT.

An optional property is used only if the obligatory properties do not provide unique identification of an object.

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