Yandex DataLens

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Questions and answers

COUNTD_APPROX

Aggregate functions

Syntax

COUNTD_APPROX( value )

Description

Returns the approximate number of unique values in the group. Faster than COUNTD, but doesn't guarantee accuracy.

Argument types:

value — Any

Return type: Number (whole)

Examples

COUNTD_APPROX([ClienID])

Data source support

Materialized Dataset, ClickHouse 1.1.