The answer entailed by any knowledge-seeking question is a knowledge relation, in a
form similar to Codd’s relations. Like Codd’s relations, knowledge relations are sets of
stored attribute-value pairs; however, knowledge relations are unlike Codd’s
abstractions in that they are polysemous: they will always participate in multiple
roles within the knowledge base, so cannot have a single formalised existence.
Knowledge relations are always automatically entailed (for the universe of discourse) in
a logical sense at the moment of formulation. As such knowledge relations are always
implicit in the dataset, even if only as an empty relation.