Enforcing Confluence of Rule Execution
Rules provide the functionality for constraint enforcement and view maintenance. A provably correct implementation of both issues based on rules, requires confluent and terminating behaviour of the rule set. In , we introduced a design theory for the static detection of these properties. The detection of confluence is based on commutativity of rule execution, called independence. In this article, we discuss the enforcement of confluence for terminating, dependent rule sets.
For a clear view on the cause of dependence, we identify a conflict set. This set is characterised by a set of dependent rules together with conditions that describe on which part of the database the rules are actually dependent. For the enforcement of confluence without re-definition of dependent rules, we define an ordering mechanism. Finally, a transformation of dependent rules into independent rules is given.
KeywordsHull Decid Klop
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