Abstract
We study inference rules for multivalued dependencies in relational databases with null values (NMVDs). The definition of NMVDs is dependent on the underlying relation schema and this is reflected syntactically by the - complementation rule which is present in all previous axiomatisation of NMVDs. The main result is a sound and complete set of inference rules in which the -axiom is the only inference rule dependent on . This result extends work of Biskup who has provided such an axiomatisation in the absence of null values. It is proven that the set is minimal in a very strong sense. In fact, none of its rules can be omitted without losing the ability to infer all trivial NMVDs.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
