ClickHouse/docs/zh/sql-reference/aggregate-functions/reference/topkweighted.md
2021-03-25 17:09:19 +08:00

912 B
Raw Blame History

toc_priority
109

topKWeighted

Similar to topK but takes one additional argument of integer type - weight. Every value is accounted weight times for frequency calculation.

Syntax

topKWeighted(N)(x, weight)

Parameters

  • N — The number of elements to return.

Arguments

  • x The value.
  • weight — The weight. UInt8.

Returned value

Returns an array of the values with maximum approximate sum of weights.

Example

Query:

SELECT topKWeighted(10)(number, number) FROM numbers(1000)

Result:

┌─topKWeighted(10)(number, number)──────────┐
│ [999,998,997,996,995,994,993,992,991,990] │
└───────────────────────────────────────────┘