Containment and Optimization of Object-Preserving Conjunctive Queries.
Edward P. F. ChanRon van der MeydenPublished in: SIAM J. Comput. (2000)
Keyphrases
- conjunctive queries
- query answering
- query evaluation
- integrity constraints
- query language
- query containment
- data complexity
- np complete
- containment of conjunctive queries
- query rewriting
- special case
- data exchange
- decision procedures
- unions of conjunctive queries
- datalog programs
- probabilistic databases
- dl lite
- data objects
- conjunctive query containment
- boolean expressions
- regular path queries
- relational queries
- query processing
- answering queries using views
- objective function
- conjunctive regular path queries
- conp complete
- relational databases