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  1. Calcite
  2. CALCITE-2035

Add APPROX_COUNT_DISTINCT aggregate function

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 1.15.0
    • Component/s: None
    • Labels:
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      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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              • Assignee:
                julianhyde Julian Hyde
                Reporter:
                julianhyde Julian Hyde
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                • Created:
                  Updated:
                  Resolved: