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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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    • Type: Icon: Improvement Improvement
    • Resolution: Duplicate
    • Priority: Icon: Major - P3 Major - P3
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    • Affects Version/s: None
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    • Query Optimization

      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.

            Assignee:
            backlog-query-optimization [DO NOT USE] Backlog - Query Optimization
            Reporter:
            ben.shteinfeld@mongodb.com Ben Shteinfeld
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              Created:
              Updated:
              Resolved: