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Recommendation based on preliminary analysis of effect of non-left-deep trees on query processing algorithms

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• Limiting the search space for optimization for join queries
  • Search space limitation for the join trees:

    We will limit our ordering of joins to left-deep join trees

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  • Note: the "limited" search space is still very large

    Join N relations: The number of left-deep join trees of N relations is equal to N ! N! is an exponential function !!!

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  • We will study an algorithm to find the best left-deep join tree next.....