ClickHouse/docs/en/sql-reference/aggregate-functions/reference/topkweighted.md
Ivan Blinkov 7170f3c534
[docs] split aggregate function and system table references (#11742)
* prefer relative links from root

* wip

* split aggregate function reference

* split system tables
2020-06-18 11:24:31 +03:00

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---
toc_priority: 109
---
# topKWeighted {#topkweighted}
Similar to `topK` but takes one additional argument of integer type - `weight`. Every value is accounted `weight` times for frequency calculation.
**Syntax**
``` sql
topKWeighted(N)(x, weight)
```
**Parameters**
- `N` — The number of elements to return.
**Arguments**
- `x` The value.
- `weight` — The weight. [UInt8](../../../sql-reference/data-types/int-uint.md).
**Returned value**
Returns an array of the values with maximum approximate sum of weights.
**Example**
Query:
``` sql
SELECT topKWeighted(10)(number, number) FROM numbers(1000)
```
Result:
``` text
┌─topKWeighted(10)(number, number)──────────┐
│ [999,998,997,996,995,994,993,992,991,990] │
└───────────────────────────────────────────┘
```