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Explain the distinction between disjoint and overlapping constraints.
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Source:- stackoverflow

The disjoint rule states an entity instance of a supertype can only be a member of one subtype. The overlap rule states an entity instance of a supertype can be a member of multiple subtypes.

Example of disjoint rule: Instance of Super-type Animal can only be member of exactly one of these Sub-types being Panda, Cheetah and Dog Disjoint Union , (An animal can either be Panda or be Dog or be Cheetah but can't be any two or more at the same time)

Example of overlap rule: Instance of Super-type Person can be member of multiple Sub-types being Woman, Driver and Engineer Overlapping Union , (A person can be a Woman and that same Woman can be Driver and that same Woman can be Engineer at the same time)

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