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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

    • Sub-task
    • Status: Closed
    • Major
    • Resolution: Fixed
    • None
    • 4.8.0
    • None
    • None

    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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            larsh Lars Hofhansl
            larsh Lars Hofhansl
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