First-order queries on classes of structures with bounded expansion.
Wojciech KazanaLuc SegoufinPublished in: Log. Methods Comput. Sci. (2020)
Keyphrases
- unions of conjunctive queries
- data exchange
- conjunctive queries
- query processing
- answering queries
- web search engines
- query language
- response time
- tractable cases
- first order logic
- higher order
- query evaluation
- query answering
- transitive closure
- relational queries
- database
- data sources
- query logs
- complex queries
- user queries
- data structure
- query formulation
- database systems
- polynomial size
- bounded treewidth
- query containment
- efficient processing
- relational algebra
- search queries
- np complete