This paper extends earlier research on hash-join algorithms to a multiprocessor architecture. Implementations of a number of centralized join algorithms are described and measured. Evaluation of these algorithms served to verify earlier analytical results. In addition, they demonstrate that bit vector filtering provides dramatic improvement in the performance of all algorithms including the sor...

Adaptive query processors make decisions as to the most effective evaluation strategy for a query based on feedback received while the query is being evaluated. In essence, any of the decisions made by the optimizer (e.g., on operator order or on which operators to use) may be revisited in an adaptive query processor. This paper focuses on changes to physical operators (e.g., the specific join ...

In global computing applications the availability of a mechanism for some form of committed choice can be useful, and sometimes necessary. It can conveniently handle, e.g., distributed agreements and negotiations with nested choice points. We propose a linguistic extension of the Join calculus for programming nested commits, called Committed Join (cJoin). It provides primitives for explicit abo...

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