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  1. Phoenix
  2. PHOENIX-258 Use skip scan when SELECT DISTINCT on leading row key column(s)
  3. PHOENIX-2987

DISTINCT/GROUP BY optimization not correct for null values in key parts

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    Details

    • Type: Sub-task
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 4.8.0
    • Labels:
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      Description

      During forward scans with the DistinctPrefix filter set null values are not returned.
      The reason is that that lastKey is initialized with ByteUtil.EMPTY_BYTE_ARRAY, which happens to the equal to a null value in a key part. So the filter determines it has seen the value before.

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        1. 2987.txt
          2 kB
          Lars Hofhansl

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            • Assignee:
              lhofhansl Lars Hofhansl
              Reporter:
              lhofhansl Lars Hofhansl
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              Dates

              • Created:
                Updated:
                Resolved: