TAILIEUCHUNG - MauveDB: Supporting Model-based User Views in Database Systems

The widespread deployment of sensors is transforming the physical world into a computing platform. Modern sensors not only respond to physical signals to produce data, they also embed computing and communication capabilities. They are thus able to store, process locally and transfer the data they produce. Still, at the heart of each sensor, a set of signal processing functions transform physical signals such as heat, light, sound, pressure,. | MauveDB Supporting Model-based User Views in Database Systems Amol Deshpande amol@ University of Maryland ABSTRACT Real-world data especially when generated by distributed measurement infrastructures such as sensor networks tends to be incomplete imprecise and erroneous making it impossible to present it to users or feed it directly into applications. The traditional approach to dealing with this problem is to first process the data using statistical or probabilistic models that can provide more robust interpretations of the data. Current database systems however do not provide adequate support for applying models to such data especially when those models need to be frequently updated as new data arrives in the system. Hence most scientists and engineers who depend on models for managing their data do not use database systems for archival or querying at all at best databases serve as a persistent raw data store. In this paper we define a new abstraction called modelbased views and present the architecture of MauveDB the system we are building to support such views. Just as traditional database views provide logical data independence model-based views provide independence from the details of the underlying data generating mechanism and hide the irregularities of the data by using models to present a consistent view to the users. MauveDB supports a declarative language for defining model-based views allows declarative querying over such views using SQL and supports several different materialization strategies and techniques to efficiently maintain them in the face of frequent updates. We have implemented a prototype system that currently supports views based on regression and interpolation using the Apache Derby open source DBMS and we present results that show the utility and performance benefits that can be obtained by supporting several different types of modelbased views in a database system. 1. INTRODUCTION modoel madl noun a simplified description .

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