Foundations of logic programming
Foundations of logic programming
Principles of database and knowledge-base systems, Vol. I
Principles of database and knowledge-base systems, Vol. I
Pattern matching by Rs-operations: towards a unified approach to querying sequenced data
PODS '92 Proceedings of the eleventh ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
A new method for undecidability proofs of first order theories
Journal of Symbolic Computation
Reasoning about strings in databases
PODS '94 Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Domain independence and the relational calculus
Acta Informatica
Sequences, Datalog and transducers
PODS '95 Proceedings of the fourteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Languages for relational databases over interpreted structures
PODS '97 Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
PODS '98 Proceedings of the seventeenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Regular sequence operations and their use in database queries
Journal of Computer and System Sciences
A relational model of data for large shared data banks
Communications of the ACM
Handbook of Formal Languages
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
Introduction to Database Systems
Introduction to Database Systems
The AQUA Approach to Querying Lists and Trees in Object-Oriented Databases
ICDE '95 Proceedings of the Eleventh International Conference on Data Engineering
SEQ: A Model for Sequence Databases
ICDE '95 Proceedings of the Eleventh International Conference on Data Engineering
VISUAL: A Graphical Icon-Based Query Language
ICDE '96 Proceedings of the Twelfth International Conference on Data Engineering
Supporting Lists in a Data Model (A Timely Approach)
VLDB '92 Proceedings of the 18th International Conference on Very Large Data Bases
The Design and Implementation of a Sequence Database System
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Existential Second-Order Logic over Strings
LICS '98 Proceedings of the 13th Annual IEEE Symposium on Logic in Computer Science
Safety, translation and evaluation of alignment calculus
ADBIS'97 Proceedings of the First East-European conference on Advances in Databases and Information systems
Unification with Sequence Variables and Flexible Arity Symbols and Its Extension with Pattern-Terms
AISC '02/Calculemus '02 Proceedings of the Joint International Conferences on Artificial Intelligence, Automated Reasoning, and Symbolic Computation
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A string database is simply a collection of tables, the columns of which contain strings over some given alphabet. We address in this paper the issue of designing a simple, user friendly query language for string databases. We focus on the language FO(•), which is classical first order logic extended with a concatenation operator, and where quantifiers range over the set of all strings. We wish to capture all string queries, i.e., well-typed and computable mappings involving a notion of string genericity. Unfortunately, unrestricted quantification may allow some queries to have infinite output. This leads us to study the "safety" problem for FO(•), that is, how to build syntactic and/or semantic restrictions so as to obtain a language expressing only queries with finite output, hopefully all string queries. We introduce a family of such restrictions and study their expressivness and complexity. We prove that none of these languages express all string queries. We prove that a family of these languages is equivalent to a simple, tractable language that we call SriQueL, standing for String Query Language, which thus emerges a robust and natural language suitable for string querying.