Abstract
In this paper we discuss on performing flexible division queries in crisp relational databases using gradual restrictions on the values of attributes. Our approach is based on using fuzzy sets for representing the restrictions and a recently proposed approach for computing and representing the result, based on the paradigm of Representations by Levels. We show some examples of usual division query patterns with SQL based on the NOT EXISTS operator.
Authors appear in alphabetical order. All authors have participated in conceptualization and research tasks. P. Córdoba-Hidalgo carried out most of the implementation tasks under the supervision of her advisors N. Marín and D. Sánchez.
This work has been partially supported by the Andalusian Government and the European Regional Development Fund - ERDF (Fondo Europeo de Desarrollo Regional - FEDER) under grants B-TIC-145-UGR18 and P18-RT-1765, BIGDATAMED. Analisis de Datos en Medicina: de las Historias Clínicas al Big Data.
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Notes
- 1.
We shall use the term instance to refer to relation instances from now on.
- 2.
In this paper, logical expressions are those expressions of first order logic based on the use of conjunction, disjunction, negation, and comparison operators in the domains of attributes, as commonly employed in relational database queries.
- 3.
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Córdoba-Hidalgo, P., Marín, N., Sánchez, D. (2022). Flexible Division Queries Based on RL-Instances. In: Ciucci, D., et al. Information Processing and Management of Uncertainty in Knowledge-Based Systems. IPMU 2022. Communications in Computer and Information Science, vol 1602. Springer, Cham. https://doi.org/10.1007/978-3-031-08974-9_26
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DOI: https://doi.org/10.1007/978-3-031-08974-9_26
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