The Impact of Disjunction on Query Answering Under Guarded-Based Existential Rules
نویسندگان
چکیده
We give the complete picture of the complexity of conjunctive query answering under (weakly-)(frontier-)guarded disjunctive existential rules, i.e., existential rules extended with disjunction, and their main subclasses, linear rules and inclusion dependencies.
منابع مشابه
The Impact of Disjunction on Reasoning under Existential Rules: Research Summary
Datalog±is a Datalog-based language family enhanced with existential quantification in rule heads, equalities and negative constraints. Query answering over databases with respect to a Datalog± theory is generally undecidable, however several syntactic restrictions have been proposed to remedy this fact. However, a useful and natural feature however is as of yet missing from Datalog±: The abili...
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