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arXiv · 2610.15187

Join Order Enumeration and Optimization for Double-Star and Helix Join Graphs

Ansh Taneja·Ryan Marcus
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Abstract

Join ordering is classic problem in data management. We highlight the connection between structure-specific dynamic programming algorithms and the mathematical enumeration of the possible merge trees from a join graph. We present two case studies, on double-star and helix shaped join graphs, that we believe carry useful techniques for a toolbox of building structure-specific join optimizers. For the double-star case, we show how the enumeration leads directly to a significantly improved search algorithm, whereas for the helix case we show that a algorithm derived from the mathematical enumeration is not necessarily better than structure-agnostic algorithms.

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Ansh Taneja, Ryan Marcus. 2026-10-10. Join Order Enumeration and Optimization for Double-Star and Helix Join Graphs. https://arxiv.org/abs/2610.15187

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