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Create a well-defined, cross-language specification for data compute operations

There is a newer version: 0.46.1

%YAML 1.2
---
aggregate_functions:
  - name: "approx_count_distinct"
    description: >-
      Calculates the approximate number of rows that contain distinct values of the expression argument using
      HyperLogLog. This function provides an alternative to the COUNT (DISTINCT expression) function, which
      returns the exact number of rows that contain distinct values of an expression. APPROX_COUNT_DISTINCT
      processes large amounts of data significantly faster than COUNT, with negligible deviation from the exact
      result.
    impls:
      - args:
          - name: x
            value: any
        nullability: DECLARED_OUTPUT
        decomposable: MANY
        intermediate: binary
        return: i64