On Low Treewidth Approximations of Conjunctive Queries.
Pablo BarcelóLeonid LibkinMiguel RomeroPublished in: AMW (2012)
Keyphrases
- conjunctive queries
- bounded treewidth
- query answering
- np complete
- integrity constraints
- query evaluation
- data complexity
- query language
- query rewriting
- data exchange
- special case
- decision procedures
- search space
- query containment
- probabilistic databases
- datalog programs
- unions of conjunctive queries
- boolean functions
- upper bound
- database
- boolean expressions
- expressive power
- dl lite
- regular path queries
- queries using views
- tight complexity bounds
- conjunctive regular path queries