One hierarchy spawns another: graph deconstructions and the complexity classification of conjunctive queries.
Hubie ChenMoritz MüllerPublished in: CSL-LICS (2014)
Keyphrases
- conjunctive queries
- bounded treewidth
- conjunctive query containment
- query answering
- query evaluation
- np complete
- integrity constraints
- data exchange
- conp complete
- data complexity
- decision trees
- query language
- conjunctive regular path queries
- computational complexity
- query rewriting
- graph model
- datalog programs
- query containment
- boolean expressions
- probabilistic databases
- directed acyclic graph
- unions of conjunctive queries
- directed graph
- data sets