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  1. Apache Trafodion (Retired)
  2. TRAFODION-3266

UPDATE STATISTICS should use SKIP CONFLICT ACCESS when accessing the base table

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Details

    • Improvement
    • Status: Resolved
    • Major
    • Resolution: Fixed
    • 2.4
    • 2.4
    • sql-cmu
    • None

    Description

      Today, UPDATE STATISTICS uses READ UNCOMMITTED ACCESS when accessing the base table. Unfortunately, our engine maps this to READ COMMITTED ACCESS. In a scenario where data ingest happens continuously, this may lead to transaction conflicts between the full table scan done by UPDATE STATISTICS and data ingest transactions that wish to commit.

      By changing UPDATE STATISTICS to use SKIP CONFLICT ACCESS, we can avoid such conflicts.

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              dbirdsall Dave Birdsall
              dbirdsall Dave Birdsall
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