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  1. Core Server
  2. SERVER-59861

Investigate if/why scans over small string fields are faster than scans over integers

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    • Icon: Task Task
    • Resolution: Cannot Reproduce
    • Icon: Major - P3 Major - P3
    • None
    • None
    • Query Execution
    • None
    • QE 2021-10-04

    Description

      timour.katchaounov has noticed that for a collection with fields {f_0, f_1, f_2, f_3, f_4}, a collection scan over all the documents is 1.5x - 2x faster when each field is a small string compared to when each field is an integer.

      The goal of this ticket is to investigate this, and if it's confirmed to be a real performance difference, determine why the integer comparisons are slower. We should test both the classic engine and SBE to determine if the regression is engine-specific, or something more fundamental to the execution system.

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            bikash.chandra@mongodb.com Bikash Chandra (Inactive)
            kyle.suarez@mongodb.com Kyle Suarez
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