Eecient Self-maintenance of Materialized Views


We address the problem of incrementallymaintaining a materialized view using the view instance and the update but with only limited access to the base data. We give necessary and su cient conditions for self-maintainability (handling updates without looking at all base data) for conjunctive-query (CQ) views. These conditions, which we call Complete Tests for Self-Maintainability or CTSM in short, are generated at view-de nition time and are expressed as safe, nonrecursive Datalog queries. We show both a direct approach that yields surprisingly simple CTSM's for a class of CQ views with self-joins, when no knowledge of the base data is available, and a query-containment-based approach that can be systematically used to nd CTSM's for more complex CQ views with or without additional knowledge about the base data.

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@inproceedings{Huyn1996EecientSO, title={Eecient Self-maintenance of Materialized Views}, author={Nam Huyn}, year={1996} }