Keyphrases
- expressive power
- deductive databases
- query answering
- datalog programs
- logic programming
- query language
- social bookmarking
- transitive closure
- integrity constraints
- data complexity
- existentially quantified
- programming language
- containment of conjunctive queries
- database languages
- neural network
- information systems
- information retrieval
- function free horn
- dl programs
- data sets
- relational query languages
- relational algebra
- query evaluation
- object oriented
- special case
- case study
- real world