Stochastic Optimization of Querying Distributed Databases Ii. Solving Stochastic Optimization
نویسندگان
چکیده
General stochastic query optimization (GSQO) problem for multiple join — join of p relations which are stored at p different sites — is presented. GSQO problem leads to a special kind of nonlinear programming problem (P ). Problem (P ) is solved by using a constructive method. A sequence converging to the solution of the optimization problem is built. Two algorithms for solving optimization problem (P ) are proposed.
منابع مشابه
Stochastic Optimization of Querying Distributed Databases I. Theory of Four Relations Join
Stochastic query optimization problem for multiple join is addressed. In Part I two sites model of Drenick and Smith (1993) is extended to four relations stored at four different sites. Our model leads to a special kind of nonlinear optimization problem (P ). It is proved (Theorem 5.1) that this problem has at least one solution. In Part II an ad hoc constructive model for solving problem (P ) ...
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