Abstract
In this paper we present a model of functional access to data that, we argue, is suitable for modeling a class of data repositories characterized by functional access, such as web sites. We discuss the problem of modeling such data sources as a set of relations, of determining whether a given query expressed on these relations can be translated into a combination of functions defined by the data sources, and of finding an optimal plan to do so.
We show that, if the data source is modeled as a single relation, an optimal plan can be found in a time linear in the number of functions in the source but, if the source is modeled as a number of relations that can be joined, finding the optimal plan is NP-hard.
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Santini, S., Gupta, A. (2004). Modeling Functional Data Sources as Relations. In: Atzeni, P., Chu, W., Lu, H., Zhou, S., Ling, TW. (eds) Conceptual Modeling – ER 2004. ER 2004. Lecture Notes in Computer Science, vol 3288. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-30464-7_6
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DOI: https://doi.org/10.1007/978-3-540-30464-7_6
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