ClickHouse/docs/zh/sql-reference/aggregate-functions/reference/grouparraymovingsum.md

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---
toc_priority: 113
---
# groupArrayMovingSum {#agg_function-grouparraymovingsum}
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计算输入值的移动和。
**语法**
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``` sql
groupArrayMovingSum(numbers_for_summing)
groupArrayMovingSum(window_size)(numbers_for_summing)
```
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该函数可以将窗口大小作为参数。 如果未指定,则该函数的窗口大小等于列中的行数。
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**参数**
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- `numbers_for_summing` — [表达式](../../../sql-reference/syntax.md#syntax-expressions) 生成数值数据类型值。
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- `window_size` — 窗口大小。
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**返回值**
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- 与输入数据大小相同的数组。
对于输入数据类型是[Decimal](../../../sql-reference/data-types/decimal.md) 数组元素类型是 `Decimal128`
对于其他的数值类型, 获取其对应的 `NearestFieldType`
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**示例**
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样表:
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``` sql
CREATE TABLE t
(
`int` UInt8,
`float` Float32,
`dec` Decimal32(2)
)
ENGINE = TinyLog
```
``` text
┌─int─┬─float─┬──dec─┐
│ 1 │ 1.1 │ 1.10 │
│ 2 │ 2.2 │ 2.20 │
│ 4 │ 4.4 │ 4.40 │
│ 7 │ 7.77 │ 7.77 │
└─────┴───────┴──────┘
```
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查询:
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``` sql
SELECT
groupArrayMovingSum(int) AS I,
groupArrayMovingSum(float) AS F,
groupArrayMovingSum(dec) AS D
FROM t
```
``` text
┌─I──────────┬─F───────────────────────────────┬─D──────────────────────┐
│ [1,3,7,14] │ [1.1,3.3000002,7.7000003,15.47] │ [1.10,3.30,7.70,15.47] │
└────────────┴─────────────────────────────────┴────────────────────────┘
```
``` sql
SELECT
groupArrayMovingSum(2)(int) AS I,
groupArrayMovingSum(2)(float) AS F,
groupArrayMovingSum(2)(dec) AS D
FROM t
```
``` text
┌─I──────────┬─F───────────────────────────────┬─D──────────────────────┐
│ [1,3,6,11] │ [1.1,3.3000002,6.6000004,12.17] │ [1.10,3.30,6.60,12.17] │
└────────────┴─────────────────────────────────┴────────────────────────┘
```