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  1. MariaDB Server
  2. MDEV-4120

UNIQUE indexes should not be considered for loose index scan

Details

    • Task
    • Status: Closed (View Workflow)
    • Minor
    • Resolution: Fixed
    • 10.0.5
    • None
    • None

    Description

      Currently the loose scan code in opt_range.cc considers all indexes as possible for the access method. Due to inexact statistics it may happen that a loose scan is selected over a unique index.

      This is clearly wrong since a "loose scan" over a unique index will read the same keys as a direct index scan, but the loose scan has more overhead.

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          relates to

          Bug - A problem which impairs or prevents the functions of the product. MDEV-7118 Anemometer stop working after upgrade to from 5.6 to 10.0

          • Critical - Crashes, loss of data, severe memory leak.
          • Closed

          Activity

            Transition Time In Source Status Execution Times
            Timour Katchaounov (Inactive) made transition -
            Open In Progress
            		120d 3h 45m 1
            Sergei Petrunia made transition -
            In Progress Stalled
            		77d 20h 13m 1
            Timour Katchaounov (Inactive) made transition -
            Stalled Closed
            		3d 23h 35m 1

            People

              timour Timour Katchaounov (Inactive)
              timour Timour Katchaounov (Inactive)
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              Dates

                Created:
                Updated:
                Resolved:

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