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Query Evaluation Techniques for Large Databases (5,8)

Goetz Graefe

Summary by: Steve Gribble and Armando Fox

One-line summary: Discussion of the implementation, performance and optimizations for various kinds of join algorithms, and a few words on query scheduling to minimize I/O cost.

Overview/Main Points

Join algorithms Optimal query scheduling


I/O reduction is the name of the game; nested loop, merge, and hash join algorithms are I/O intensive, so optimizations for them (as well as optimal query scheduling, which matters now a lot more than it used to) are a bunch of hacks to reduce I/O costs.


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