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  1. Core Server
  2. SERVER-79635

[CQF] Consider the number of projections produced by a PhysicalScan when determining its cost

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    • Icon: Improvement Improvement
    • Resolution: Duplicate
    • Icon: Major - P3 Major - P3
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    • Query Optimization

    Description

      Currently the cost of a PhysicalScan node (and Seek and IndexScan) is a function of its cardinality estimate and startup/marginal cost coefficients. It ignores the number of projections it must produce. This leads to plans that incorrectly have identical costs according to the cost model, but in reality have different runtimes.

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            backlog-query-optimization Backlog - Query Optimization
            ben.shteinfeld@mongodb.com Ben Shteinfeld
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