An amateur's introduction to recursive query processing strategies
SIGMOD '86 Proceedings of the 1986 ACM SIGMOD international conference on Management of data
Bounds on the propagation of selection into logic programs
PODS '87 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART 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
Decidable optimization problems for database logic programs
STOC '88 Proceedings of the twentieth annual ACM symposium on Theory of computing
Expressiveness of restricted recursive queries
STOC '89 Proceedings of the twenty-first annual ACM symposium on Theory of computing
On Datalog vs. polynomial time (extended abstract)
PODS '91 Proceedings of the tenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
On the equivalence of recursive and nonrecursive datalog programs
PODS '92 Proceedings of the eleventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Expressive power of query languages
Theoretical studies in computer science
Proceedings of the 30th IEEE symposium on Foundations of computer science
On the expressive power of datalog: tools and a case study
PODS '90 Proceedings of the ninth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Decidability and undecidability results for boundedness of linear recursive queries
Proceedings of the seventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
The complexity of relational query languages (Extended Abstract)
STOC '82 Proceedings of the fourteenth annual ACM symposium on Theory of computing
Perspectives on database theory
ACM SIGACT News
Transitive closure and recursive Datalog implemented on clusters
Proceedings of the 15th International Conference on Extending Database Technology
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We show that there are Datalog( ≠ ) queries on graphs (i.e., the extensional database contains a single binary relation) that require recursively defined predicates of arbitrarily large width. More specifically, we prove that fixed subgraph homeomorphism queries require width of recursively defined predicates which is at least equal to the number of arcs in the pattern graph.