# How to Make SQL Stand for String Query Language

@inproceedings{Grahne1999HowTM, title={How to Make SQL Stand for String Query Language}, author={G{\"o}sta Grahne and Emmanuel Waller}, booktitle={DBPL}, year={1999} }

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…

## 9 Citations

### Definable relations and first-order query languages over strings

- Computer ScienceJACM
- 2003

This article studies analogs of classical relational calculus in the context of strings, and shows that by choosing the string vocabulary carefully, one gets string logics that have desirable properties: computable evaluation and normal forms.

### String operations in query languages

- Computer SciencePODS '01
- 2001

The space between relational calculi with support for string operations is explored, and two intermediate languages are considered: the first extends the base language with functions that trim/add leading characters, and the other extends it by adding the full power of regular-expression pattern-matching.

### Query Languages for Sequence Databases: Termination and Complexity

- Computer ScienceIEEE Trans. Knowl. Data Eng.
- 2001

The main idea is to use safe recursion to control and limit unsafe recursion and the definition of a finite form of recursion, called domain-bounded recursions, and a characterization of its complexity and expressive power.

### Expressiveness within Sequence Datalog

- Computer SciencePODS
- 2021

This work considers classical features of Datalog programs, such as negation, recursion, intermediate predicates, and relations of higher arities, and considers new features that are useful for sequences, notably, equations between path expressions, and "packing''.

### Avoiding Infinite Loops in the Solving of Equations Involving Sequence Variables and Terms with Flexible Arity Function Symbols

- Computer Science

This paper presents a simple method for checking if a branch will lead to a loop, based on an abstraction of the original unification by a Diophantine equation on the sizes of the terms involved.

### Adding string processing capabilities to data management systems

- Computer ScienceProceedings Seventh International Symposium on String Processing and Information Retrieval. SPIRE 2000
- 2000

The work continues the development of the Alignment Declaration language, the proposal for specifying string relations, by presenting a new and improved method for evaluating the queries and analysing their finiteness.

### Pattern Unification with Sequence Variables, Flexible Arity Symbols

- Computer ScienceElectron. Notes Theor. Comput. Sci.
- 2002

### Unification with Sequence Variables and Flexible Arity Symbols and Its Extension with Pattern-Terms

- MathematicsAISC
- 2002

A minimal and complete unification procedure for a theory with individual and sequence variables, free constants and free fixed and flexible arity function symbols is described and a brief overview…

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