Tractable Orders for Direct Access to Ranked Answers of Conjunctive Queries.
Nofar CarmeliNikolaos TziavelisWolfgang GatterbauerBenny KimelfeldMirek RiedewaldPublished in: ACM Trans. Database Syst. (2023)
Keyphrases
- conjunctive queries
- np complete
- bounded treewidth
- queries using views
- query answering
- query evaluation
- complexity of query answering
- integrity constraints
- data complexity
- query language
- data exchange
- datalog programs
- query containment
- hypertree decomposition
- query answers
- special case
- probabilistic databases
- query rewriting
- computational complexity
- conjunctive query containment
- answering queries
- fixed parameter tractable
- np hard
- dl lite
- boolean expressions
- conjunctive regular path queries
- unions of conjunctive queries
- decision procedures
- deductive databases
- knowledge representation
- conp complete
- constraint satisfaction problems
- tight complexity bounds
- query processing
- lower bound