Keyphrases
- boolean algebra
- set theory
- relation algebra
- algebraic structure
- classical logic
- data model
- modal logic
- information retrieval
- logic programming
- expressive power
- computational properties
- query language
- database
- formal theory
- abductive reasoning
- algebraic expressions
- delay insensitive
- algebraic operators
- logical framework
- theorem prover
- relational algebra
- logic programs
- search engine
- databases