Equivalence of Keyed Relational Schemas by Conjunctive Queries.
Joseph AlbertYannis E. IoannidisRaghu RamakrishnanPublished in: J. Comput. Syst. Sci. (1999)
Keyphrases
- conjunctive queries
- relational schema
- schema mappings
- query containment
- integrity constraints
- datalog programs
- data exchange
- functional dependencies
- xml schema
- query answering
- database schema
- relational data
- entity relationship
- query evaluation
- query language
- conceptual schema
- relational databases
- data complexity
- xml data
- normal form
- object oriented
- data integration
- query rewriting
- relational model
- decision procedures
- relational database systems
- np complete
- data model
- special case
- xml documents
- data management
- xml queries
- transformation rules
- regular expressions
- query optimization
- knowledge representation
- transitive closure
- domain knowledge
- complex objects
- conceptual model
- databases