ClickHouse/docs/zh/sql-reference/aggregate-functions/reference/anyheavy.md
2021-03-25 17:09:20 +08:00

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---
toc_priority: 103
---
# anyHeavy {#anyheavyx}
选择一个频繁出现的值,使用[heavy hitters](http://www.cs.umd.edu/~samir/498/karp.pdf) 算法。 如果某个值在查询的每个执行线程中出现的情况超过一半,则返回此值。 通常情况下,结果是不确定的。
``` sql
anyHeavy(column)
```
**参数**
- `column` The column name。
**示例**
使用 [OnTime](../../../getting-started/example-datasets/ontime.md) 数据集,并选择在 `AirlineID` 列任何频繁出现的值。
查询:
``` sql
SELECT anyHeavy(AirlineID) AS res
FROM ontime;
```
结果:
``` text
┌───res─┐
│ 19690 │
└───────┘
```