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  1. Calcite
  2. CALCITE-2035

Add APPROX_COUNT_DISTINCT aggregate function

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Details

    • Bug
    • Status: Closed
    • Major
    • Resolution: Fixed
    • None
    • 1.15.0
    • None
    • None

    Description

      Add APPROX_COUNT_DISTINCT aggregate function. The effect of APPROX_COUNT_DISTINCT(args) is the same as COUNT(DISTINCT args) but the planner may generate approximate results (e.g. by using HyperLogLog).

      Note "may" not "must", above: the planner may choose a plan that returns exact results.

      This is a step towards CALCITE-1588, which would allow an APPROXIMATE clause and specify in more detail the degree of approximation allowed.

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          relates to

          Bug - A problem which impairs or prevents the functions of the product. CALCITE-1588 Add SQL syntax to allow approximate LIMIT and distinct-COUNT

          • Major - Major loss of function.
          • Open

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              julianhyde Julian Hyde
              julianhyde Julian Hyde
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              Dates

                Created:
                Updated:
                Resolved: