First-order unification using variable-free relational algebra.
Emilio Jesús Gallego AriasJames LiptonJulio MariñoPablo NogueiraPublished in: UNIF (2008)
Keyphrases
- relational algebra
- first order logic
- expressive power
- query language
- data model
- relational model
- normal form
- relational database systems
- complex objects
- relational calculus
- relational data model
- relational operators
- transitive closure
- database query languages
- horn clauses
- probabilistic databases
- data mining
- database
- incomplete information
- query evaluation
- knowledge representation
- expert systems
- data structure
- databases
- null values
- algebraic operations