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

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---
toc_priority: 109
---
# topKWeighted {#topkweighted}
类似于 `topK` 但需要一个整数类型的附加参数 - `weight`。 每个输入都被记入 `weight` 次频率计算。
**语法**
``` sql
topKWeighted(N)(x, weight)
```
**参数**
- `N` — 要返回的元素数。
**参数**
- `x` (要计算频次的)值。
- `weight` — 权重。 [UInt8](../../../sql-reference/data-types/int-uint.md)类型。
**返回值**
返回具有最大近似权重总和的值数组。
**示例**
查询:
``` sql
SELECT topKWeighted(10)(number, number) FROM numbers(1000)
```
结果:
``` text
┌─topKWeighted(10)(number, number)──────────┐
│ [999,998,997,996,995,994,993,992,991,990] │
└───────────────────────────────────────────┘
```