Keyphrases
- conjunctive queries
- query answering
- integrity constraints
- query evaluation
- np complete
- query language
- data complexity
- special case
- data exchange
- query rewriting
- decision procedures
- query containment
- relational queries
- datalog programs
- conjunctive query containment
- database systems
- consistent query answering
- satisfiability problem
- schema mappings
- expressive power
- data model
- relational databases
- lower bound
- dl lite
- bounded treewidth
- regular path queries
- database