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Extended relational operators for statistical data manipulations in medical databases.

H H Yao·T S Yamashita
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Abstract

Conventional relational database management systems fail to address three features of statistical data management in a biomedical/clinical database, namely, that (1) statistical and medical data (SMD) require a great deal of space and need to be stored in a reduced form with minimal duplication; indeed, SMD have many derived/calculated and summary statistics that make the number of attributes in a relation (i.e., a set of records) grow rapidly and dynamically; (2) most SMD have hierarchical structures that are difficult to manage using the relational data model since SMD are stored in separate relations for duplication and space considerations; and (3) the management of SMD is made easier if it is possible to reorganize relations or group data, a capability lacking in conventional relational database management systems. In this paper, we (1) introduce five extended relational operators, (lattice) NEST, (lattice) UNNEST, MERGE, SPREAD, and GEN, to reorganize relations; (2) integrate the extended operators with conventional relational algebra and introduce the concept of the lattice relational model; and (3) give applications of the extended relational operators and the lattice relational model in solving the problems of statistical data manipulation in medical databases.

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Database Management SystemsHospital RecordsHumansMathematical ComputingMedical Informatics ComputingSoftwareJournal Article

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BibTeXRIS

H H Yao, T S Yamashita. 1989. Extended relational operators for statistical data manipulations in medical databases.. https://doi.org/10.1016/0010-4809(89)90072-4

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