Tractable Orders for Direct Access to Ranked Answers of Conjunctive Queries.
Nofar CarmeliNikolaos TziavelisWolfgang GatterbauerBenny KimelfeldMirek RiedewaldPublished in: PODS (2021)
Keyphrases
- conjunctive queries
- np complete
- bounded treewidth
- queries using views
- query answering
- query evaluation
- complexity of query answering
- data complexity
- integrity constraints
- query language
- hypertree decomposition
- special case
- query containment
- data exchange
- query rewriting
- decision procedures
- probabilistic databases
- np hard
- boolean expressions
- query answers
- fixed parameter tractable
- computational complexity
- conp complete
- relational queries
- datalog programs
- dl lite
- answering queries
- optimal solution
- tree width
- satisfiability problem
- deductive databases
- schema mappings
- expressive power
- constraint satisfaction problems
- conjunctive query containment
- conjunctive regular path queries