groupArrayMovingSum

引入版本：v20.1.0 计算输入值的滑动和。该函数可将窗口大小作为参数传入。若未指定，则窗口大小默认为列中的行数。语法

groupArrayMovingSum(numbers_for_summing)
groupArrayMovingSum(window_size)(numbers_for_summing)

参数

window_size — 计算窗口的大小。若未指定，函数会将窗口大小设为该列中的行数。UInt64

Arguments

numbers_for_summing — 结果为数值数据类型值的表达式。(U)Int* 或 Float* 或 Decimal

返回值 返回一个与输入数据大小和类型相同的数组。Array 示例 使用示例

Query

CREATE TABLE t
(
    `int` UInt8,
    `float` Float32,
    `dec` Decimal32(2)
)
ENGINE = Memory;

INSERT INTO t VALUES (1, 1.1, 1.10), (2, 2.2, 2.20), (4, 4.4, 4.40), (7, 7.77, 7.77);

SELECT
    groupArrayMovingSum(int) AS I,
    groupArrayMovingSum(float) AS F,
    groupArrayMovingSum(dec) AS D
FROM t;

Response

┌─I──────────┬─F───────────────────────────────┬─D──────────────────────┐
│ [1,3,7,14] │ [1.1,3.3000002,7.7000003,15.47] │ [1.10,3.30,7.70,15.47] │
└────────────┴─────────────────────────────────┴────────────────────────┘

指定窗口大小

Query

SELECT
    groupArrayMovingSum(2)(int) AS I,
    groupArrayMovingSum(2)(float) AS F,
    groupArrayMovingSum(2)(dec) AS D
FROM t;

Response

┌─I──────────┬─F───────────────────────────────┬─D──────────────────────┐
│ [1,3,6,11] │ [1.1,3.3000002,6.6000004,12.17] │ [1.10,3.30,6.60,12.17] │
└────────────┴─────────────────────────────────┴────────────────────────┘

​groupArrayMovingSum

groupArrayMovingSum