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  1. Hive
  2. HIVE-13196

UDFLike: reduce Regex NFA sizes

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Details

    • Improvement
    • Status: Closed
    • Minor
    • Resolution: Fixed
    • 1.2.1, 1.3.0, 2.0.0, 2.1.0
    • 2.1.0
    • UDF
    • None

    Description

      The NFAs built from complex regexes in UDFLike are extremely complex and spend a lot of time doing simple expression matching with no backtracking.

      Prevent NFA -> DFA explosion by using reluctant regex matches instead of greedy matches.

      Attachments

        1. HIVE-13196.1.patch
          0.6 kB
          Gopal Vijayaraghavan
        2. HIVE-13196.1.patch
          0.6 kB
          Gopal Vijayaraghavan

        Issue Links

          is required by

          Bug - A problem which impairs or prevents the functions of the product. HIVE-14349 Vectorization: LIKE should anchor the regexes

          • Major - Major loss of function.
          • Closed

          Activity

            People

              gopalv Gopal Vijayaraghavan
              gopalv Gopal Vijayaraghavan
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              Dates

                Created:
                Updated:
                Resolved: