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To get more meaning of incomplete information,a predicate way is proposed torepresent the nulls.The concepts of functional and multivalued dependencies areextended in the environment which allows nulls in a database relation.The inferencerules which can be applied to the extended dependencies are investigated.Finally it isshown that the rules are complete for the family of extended functional and multivalueddependencies.
To get more meaning of incomplete information, a predicate way is proposed torepresent the nulls.The concepts of functional and multivalued dependencies areextended in the environment which allows nulls in a database. The inferencerules which can be applied to the extended dependencies are investigated .Finally it isshown that the rules are complete for the family of extended functional and multivalued dependencies.