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Data extraction and ad hoc query of an entity-attribute-value database.

P M Nadkarni·C Brandt
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Abstract

Entity--attribute--value (EAV) tables form the major component of several mainstream electronic patient record systems (EPRSs). Such systems have been optimized for real-time retrieval of individual patient data. Data warehousing, on the other hand, involves cross-patient data retrieval based on values of patient attributes, with a focus on ad hoc query. Attribute-centric query is inherently more difficult when data are stored in EAV form than when they are stored conventionally. The authors illustrate their approach to the attribute-centric query problem with ACT/DB, a database for managing clinical trials data. This approach is based on metadata supporting a query front end that essentially hides the EAV/non-EAV nature of individual attributes from the user. The authors' work does not close the query problem, and they identify several complex subproblems that are still to be solved.

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Clinical Trials as TopicDatabase Management SystemsHumansInformation Storage and RetrievalMedical Records Systems, ComputerizedUser-Computer InterfaceJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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P M Nadkarni, C Brandt. Data extraction and ad hoc query of an entity-attribute-value database.. https://doi.org/10.1136/jamia.1998.0050511

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