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title: “ApproximateUnique”

ApproximateUnique

Transforms for estimating the number of distinct elements in a collection or the number of distinct values associated with each key in a collection of key-value pairs.

Examples

See BEAM-7703 for updates.

Related transforms

• HllCount estimates the number of distinct elements and creates re-aggregatable sketches using the HyperLogLog++ algorithm.
• Count counts the number of elements within each aggregation.
• Distinct