Undecidability of the Positive Calculus of Relations with Transitive Closure and Difference: Hypothesis Elimination Using Graph Loops.
Yoshiki NakamuraPublished in: RAMiCS (2024)
Keyphrases
- transitive closure
- relational calculus
- directed acyclic graph
- binary relations
- query containment
- expressive power
- relational algebra
- constraint databases
- first order logic
- recursive queries
- directed graph
- query language
- query evaluation
- exptime complete
- graph theoretic
- spatial databases
- relational model
- description logics
- random variables
- data model
- structured data