Planning to Gather Information

We describe Occam, a query planning algorithm that determines the best way to integrate data from di erent sources. As input, Occam takes a library of site descriptions and a user query. As output, Occam automatically generates one or more plans that encode alternative ways to gather the requested information. Occam has several important features: (1) it integrates both legacy systems and full relational databases with an e cient, domain-independent, query-planning algorithm, (2) it reasons about the capabilities of di erent information sources, (3) it handles partial goal satisfaction i.e., gathers as much data as possible when it can't gather exactly all that the user requested, (4) it is both sound and complete, (5) it is e cient. We present empirical results demonstrating Occam's performance on a variety of information gathering tasks.

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