A Two-stage Stochastic View Selection Problem in Database Management Systems
نویسندگان
چکیده
We present a study of the two-stage stochastic view selection problem in database management systems. The objective is to minimize processing times of the given queries subject to a storage limit. We assume that the queries are given in two or more workloads. We propose a two-stage stochastic programming (SP) model for this problem and study the structure and properties of its extensive form, which is an integer programming (IP) model. We use these properties to remove variables and constraints from this IP model, and obtain a smaller model with the same optimal solution. This allows us to solve realistic-size instances of the problem using commercial IP solvers. Subsequently, we present appropriate models, and techniques to assess the value of using a two-stage SP model, and discuss the value of perfect information. We discuss the properties of these values by conducting a computational experiment.
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