Computability and logic: 3rd ed.
Computability and logic: 3rd ed.
A new recursion-theoretic characterization of the polytime functions (extended abstract)
STOC '92 Proceedings of the twenty-fourth annual ACM symposium on Theory of computing
Stratified functional programs and computational complexity
POPL '93 Proceedings of the 20th ACM SIGPLAN-SIGACT symposium on Principles of programming languages
Hereditarily-finite sets, data bases and polynomial-time computability
Informatika '91 Selected papers of the 5th Soviet-French symposium on Theoretical computer science, methods and tools for compilation, and program development
Algebraic and calculus query languages for recursively typed complex objects
PODS '89 Selected papers of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
A query language for list-based complex objects
PODS '94 Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Principles of programming with complex objects and collection types
ICDT '92 Selected papers of the fourth international conference on Database theory
The expressiveness of a family of finite set languages
Theoretical Computer Science
Bounded fixpoints for complex objects
Theoretical Computer Science
Query languages for bags and aggregate functions
Journal of Computer and System Sciences - Special issue on principles of database systems
Information and Computation
Sequences, datalog, transducers
Journal of Computer and System Sciences - Fourteenth ACM SIGACT-SIGMOD-SIGART symposium on principles of database systems
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
The power of languages for the manipulation of complex values
The VLDB Journal — The International Journal on Very Large Data Bases
On Two Forms of Structural Recursion
ICDT '95 Proceedings of the 5th International Conference on Database Theory
Tractable Iteration Mechanisms for Bag Languages
ICDT '97 Proceedings of the 6th International Conference on Database Theory
A Semi-monad for Semi-structured Data
ICDT '01 Proceedings of the 8th International Conference on Database Theory
A Mixed Modal/Linear Lambda Calculus with Applications to Bellantoni-Cook Safe Recursion
CSL '97 Selected Papers from the11th International Workshop on Computer Science Logic
UnQL: a query language and algebra for semistructured data based on structural recursion
The VLDB Journal — The International Journal on Very Large Data Bases
Semantics of linear/modal lambda calculus
Journal of Functional Programming
On the complexity of nonrecursive XQuery and functional query languages on complex values
Proceedings of the twenty-fourth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Well-definedness and semantic type-checking in the nested relational calculus and XQuery
ICDT'05 Proceedings of the 10th international conference on Database Theory
Annotated XML: queries and provenance
Proceedings of the twenty-seventh ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Proceedings of the 4th International Workshop on Logic in Databases
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XML query languages need to provide some mechanism to inspect and manipulate nodes at all levels of an input tree. In this paper we investigate the expressive power provided in this regard by structural recursion. We show that the combination of vertical recursion down a tree combined with horizontal recursion across a list of trees gives rise to a robust class of transformations: it captures the class of all primitive recursive queries. Since queries are expected to be computable in at most polynomial time for all practical purposes, we next identify a restriction of structural recursion that captures the polynomial time queries. Although this restriction is semantical in nature, and therefore undecidable, we provide an effective syntax. We also give corresponding results for list-based complex objects.