Magic sets and other strange ways to implement logic programs (extended abstract)
PODS '86 Proceedings of the fifth ACM SIGACT-SIGMOD symposium on Principles of database systems
Decidability and expressiveness aspects of logic queries
PODS '87 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
PODS '87 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
PODS '87 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Compiling separable recursions
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
Boundedness is undecidable for datalog programs with a single recursive rule
Information Processing Letters
Proof-tree transformation theorems and their applications
PODS '89 Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Linearising nonlinear recursions in polynomial time
PODS '89 Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Polynomial-time program transformations in deductive databases
PODS '90 Proceedings of the ninth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Equivalences Among Relational Expressions with the Union and Difference Operators
Journal of the ACM (JACM)
Introduction To Automata Theory, Languages, And Computation
Introduction To Automata Theory, Languages, And Computation
Optimal implementation of conjunctive queries in relational data bases
STOC '77 Proceedings of the ninth annual ACM symposium on Theory of computing
Constraints and redundancy in datalog
PODS '92 Proceedings of the eleventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Generalization of ZYT-linearizability for bilinear datalog programs
Information and Computation
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A number of optimizations have been proposed for Datalog programs involving a single intensional predicate (“single-IDB programs”). Examples include the detection of commutativity and separability ([Naug88],[RSUV89], [Ioan89a]) in linear logic programs, and the detection of ZYT-linearizability ([ZYT88], [RSUV89], [Sara89], [Sara90]) in nonlinear programs. We show that the natural generalizations of the commutativity and ZYT-linearizability problems (respectively, the sequencability and base-case linearizability problems) are undecidable. Our constructions involve the simulation of context-free grammars using single-IDB programs that have a bounded number of initialisation rules. The constructions may be used to show that containment (or equivalence) is undecidable for such programs, even if the programs are linear, or if each program contains a single recursive rule. These results tighten those of [Shmu87] and [Abit89].