Counter Strike: Generic Top-Down Join Enumeration for Hypergraphs

@article{Fender2013CounterSG,
  title={Counter Strike: Generic Top-Down Join Enumeration for Hypergraphs},
  author={Pit Fender and Guido Moerkotte},
  journal={Proc. VLDB Endow.},
  year={2013},
  volume={6},
  pages={1822-1833}
}
Finding the optimal execution order of join operations is a crucial task of today's cost-based query optimizers. There are two approaches to identify the best plan: bottom-up and top-down join enumeration. But only the top-down approach allows for branch-and-bound pruning, which can improve compile time by several orders of magnitude while still preserving optimality. For both optimization strategies, efficient enumeration algorithms have been published. However, there are two severe… 

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